Microsoft Visual C# XML: XML Reading and Writing

	XML Reading and Writing

Fundamentals of Writing to an XML File

Introduction

You may know already how to process XML files using the Document Object Model as implemented by the XmlDocument class. To go further and make XML friendlier, the .NET Framework provides many other classes for different purposes, allowing you to create and manage nodes from custom .NET classes.

Practical Learning: Introducing XML Reading

Start Microsoft Visual Studio
To create a new application, on the main menu, click FILE -> New Project...
In the middle list, click Windows Forms Application and set the Name to CollegeParkAutoRepair2
Click OK
In the Solution Explorer, right-click Form1.cs and click Rename
Type cpar.cs and press Enter
From the Menus & Toolbars section of the Toolbox, click MenuStrip and click the form

Design the menu items as follows:

MenuItem		DropDownItems
Text	Name	Text	Name	Shortcut
&File	mnuFile	&New Repair Order	mnuFileNew	Ctrl+N
		&Open Existing Order...	mnuFileOpen	Ctrl+O
		&Save Current Order	mnuFileSave	Ctrl+S
		Separator
		&Print...	mnuFilePrint	Ctrl+P
		Print Pre&view...	mnuFilePrintPreview
		Separator
		E&xit	mnuFileExit

Design the form as follows:

Control	Name	Text	Other Properties
GroupBox		Order Identification
Label		Customer Name:
TextBox	txtCustomerName
Label		Address
TextBox	txtAddress
Label		City:
TextBox	txtCity
Label		State:
TextBox	txtState
Label		ZIP Code:
TextBox	txtZIPCode		TextAlign: Right
Label		Make / Model:
TextBox	txtMake
TextBox	txtModel
Label		Year:
TextBox	txtCarYear		TextAlign: Right
Label		Problem Description:
TextBox	txtProblem
GroupBox		Parts Used
Label		Part Name
Label		Unit Price
Label		Qty
Label		Sub Total
TextBox	txtPartName1
TextBox	txtUnitPrice1	0.00	TextAlign: Right
TextBox	txtQuantity1	0	TextAlign: Right
TextBox	txtSubTotal1	0.00	TextAlign: Right Enabled: False
TextBox	txtPartName2
TextBox	txtUnitPrice2	0.00	TextAlign: Right
TextBox	txtQuantity2	0	TextAlign: Right
TextBox	txtSubTotal2	0.00	TextAlign: Right Enabled: False
TextBox	txtPartName3
TextBox	txtUnitPrice3	0.00	TextAlign: Right
TextBox	txtQuantity3	0	TextAlign: Right
TextBox	txtSubTotal3	0.00	TextAlign: Right Enabled: False
TextBox	txtPartName4
TextBox	txtUnitPrice4	0.00	TextAlign: Right
TextBox	txtQuantity4	0	TextAlign: Right
TextBox	txtSubTotal4	0.00	TextAlign: Right Enabled: False
TextBox	txtPartName5
TextBox	txtUnitPrice5	0.00	TextAlign: Right
TextBox	txtQuantity5	0	TextAlign: Right
TextBox	txtSubTotal5	0.00	TextAlign: Right Enabled: False
GroupBox		Jobs Performed
Label		Price
TextBox	txtJobPerformed1
TextBox	txtJobPrice1	0.00	TextAlign: Right
TextBox	txtJobPerformed2
TextBox	txtJobPrice2	0.00	TextAlign: Right
TextBox	txtJobPerformed3
TextBox	txtJobPrice3	0.00	TextAlign: Right
TextBox	txtJobPerformed4
TextBox	txtJobPrice4	0.00	TextAlign: Right
TextBox	txtJobPerformed5
TextBox	txtJobPrice5	0.00	TextAlign: Right
GroupBox		Order Summary
Label		Total Parts:
TextBox	txtTotalParts	0.00	TextAlign: Right
Label		Total Labor:
TextBox	txtTotalLabor	0.00	TextAlign: Right
Label		Tax Rate:
TextBox	txtTaxRate	7.75	TextAlign: Right
Label		%
Label		Tax Amount:
TextBox	txtTaxAmount	0.00	TextAlign: Right
Label		Total Order:
TextBox	txtTotalOrder	0.00	TextAlign: Right
Label		Recommendations
TextBox	txtRecommendations		Multiline: True ScrollBars: Vertical

Right-click the form and click VIEW Code

Create a method named Calculate as follows:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Xml;

namespace CollegeParkAutoRepair2
{
    public partial class Exercise : Form
    {
        public Exercise()
        {
            InitializeComponent();
        }
        
        void Calculate()
        {
            double part1UnitPrice = 0.00, part2UnitPrice = 0.00,
                   part3UnitPrice = 0.00, part4UnitPrice = 0.00,
                   part5UnitPrice = 0.00;
            double part1SubTotal, part2SubTotal, part3SubTotal,
                   part4SubTotal, part5SubTotal, totalParts;
            int part1Quantity = 0, part2Quantity = 0, part3Quantity = 0,
                   part4Quantity = 0, part5Quantity = 0;
            double job1Price = 0.00, job2Price = 0.00, job3Price = 0.00,
                   job4Price = 0.00, job5Price = 0.00;
            double totalLabor;
            double taxRate = 0.00, taxAmount, totalOrder;

            // Don't charge a part unless it is clearly identified
            if (txtPartName1.Text == "")
            {
                txtUnitPrice1.Text = "0.00";
                txtQuantity1.Text = "0";
                txtSubTotal1.Text = "0.00";
                part1UnitPrice = 0.00;
            }
            else
            {
                try
                {
                    part1UnitPrice = double.Parse(txtUnitPrice1.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Unit Price");
                    txtUnitPrice1.Text = "0.00";
                    txtUnitPrice1.Focus();
                }

                try
                {
                    part1Quantity = int.Parse(txtQuantity1.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Quantity");
                    txtQuantity1.Text = "0";
                    txtQuantity1.Focus();
                }
            }

            if (this.txtPartName2.Text == "" )
            {
                txtUnitPrice2.Text = "0.00";
                txtQuantity2.Text = "0";
                txtSubTotal2.Text = "0.00";
                part2UnitPrice = 0.00;
            }
            else
            {
                try
                {
                    part2UnitPrice = double.Parse(txtUnitPrice2.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Unit Price");
                    this.txtUnitPrice2.Text = "0.00";
                    this.txtUnitPrice2.Focus();
                }

                try
                {
                    part2Quantity = int.Parse(txtQuantity2.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Quantity");
                    txtQuantity2.Text = "0";
                    txtQuantity2.Focus();
                }
            }

            if (txtPartName3.Text == "" )
            {
                txtUnitPrice3.Text = "0.00";
                txtQuantity3.Text = "0";
                txtSubTotal3.Text = "0.00";
                part3UnitPrice = 0.00;
            }
            else
            {
                try
                {
                    part3UnitPrice = double.Parse(txtUnitPrice3.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Unit Price");
                    txtUnitPrice3.Text = "0.00";
                    txtUnitPrice3.Focus();
                }

                try
                {
                    part3Quantity = int.Parse(txtQuantity3.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Quantity");
                    txtQuantity3.Text = "0";
                    txtQuantity3.Focus();
                }
            }

            if (txtPartName4.Text == "" )
            {
                txtUnitPrice4.Text = "0.00";
                txtQuantity4.Text = "0";
                txtSubTotal4.Text = "0.00";
                part4UnitPrice = 0.00;
            }
            else
            {
                try
                {
                    part4UnitPrice = double.Parse(txtUnitPrice4.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Unit Price");
                    txtUnitPrice4.Text = "0.00";
                    txtUnitPrice4.Focus();
                }

                try
                {
                    part4Quantity = int.Parse(txtQuantity4.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Quantity");
                    txtQuantity4.Text = "0";
                    txtQuantity4.Focus();
                }
            }

            if (txtPartName5.Text == "" )
            {
                txtUnitPrice5.Text = "0.00";
                txtQuantity5.Text = "0";
                txtSubTotal5.Text = "0.00";
                part5UnitPrice = 0.00;
            }
            else
            {
                try
                {
                    part5UnitPrice = double.Parse(txtUnitPrice5.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Unit Price");
                    txtUnitPrice5.Text = "0.00";
                    txtUnitPrice5.Focus();
                }

                try
                {
                    part5Quantity = int.Parse(txtQuantity5.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Quantity");
                    txtQuantity5.Text = "0";
                    txtQuantity5.Focus();
                }
            }

            // Don't bill the customer for a job that is not specified
            if (txtJobDescription1.Text == "")
            {
                txtJobPrice1.Text = "0.00";
                job1Price = 0.00;
            }
            else
            {
                try
                {
                    job1Price = double.Parse(txtJobPrice1.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Job Price");
                    txtJobPrice1.Text = "0.00";
                    txtJobPrice1.Focus();
                }
            }

            if (txtJobDescription2.Text == "")
            {
                txtJobPrice2.Text = "0.00";
                job2Price = 0.00;
            }
            else
            {
                try
                {
                    job2Price = double.Parse(txtJobPrice2.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Job Price");
                    txtJobPrice2.Text = "0.00";
                    txtJobPrice2.Focus();
                }
            }

            if (txtJobDescription3.Text == "")
            {
                txtJobPrice3.Text = "0.00";
                job3Price = 0.00;
            }
            else
            {
                try
                {
                    job3Price = double.Parse(txtJobPrice3.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Job Price");
                    txtJobPrice3.Text = "0.00";
                    txtJobPrice3.Focus();
                }
            }

            if (txtJobDescription4.Text == "")
            {
                txtJobPrice4.Text = "0.00";
                job4Price = 0.00;
            }
            else
            {
                try
                {
                    job4Price = double.Parse(txtJobPrice4.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Job Price");
                    txtJobPrice4.Text = "0.00";
                    txtJobPrice4.Focus();
                }
            }

            if (txtJobDescription5.Text == "")
            {
                txtJobPrice5.Text = "0.00";
                job5Price = 0.00;
            }
            else
            {
                try
                {
                    job5Price = double.Parse(txtJobPrice5.Text);
                }
                catch (FormatException)
                {
                    MessageBox.Show("Invalid Job Price");
                    txtJobPrice5.Text = "0.00";
                    txtJobPrice5.Focus();
                }
            }

            part1SubTotal = part1UnitPrice * part1Quantity;
            part2SubTotal = part2UnitPrice * part2Quantity;
            part3SubTotal = part3UnitPrice * part3Quantity;
            part4SubTotal = part4UnitPrice * part4Quantity;
            part5SubTotal = part5UnitPrice * part5Quantity;

            txtSubTotal1.Text = part1SubTotal.ToString("F");
            txtSubTotal2.Text = part2SubTotal.ToString("F");
            txtSubTotal3.Text = part3SubTotal.ToString("F");
            txtSubTotal4.Text = part4SubTotal.ToString("F");
            txtSubTotal5.Text = part5SubTotal.ToString("F");

            totalParts = part1SubTotal + part2SubTotal + part3SubTotal +
                    part4SubTotal + part5SubTotal;

            totalLabor = job1Price + job2Price + job3Price +
                            job4Price + job5Price;

            try
            {
                taxRate = double.Parse(txtTaxRate.Text);
            }
            catch (FormatException)
            {
                MessageBox.Show("Invalid Tax Rate");
                txtTaxRate.Text = "7.75";
                txtTaxRate.Focus();
            }

            double totalPartsAndLabor = totalParts + totalLabor;
            taxAmount = totalPartsAndLabor * taxRate / 100;
            totalOrder = totalPartsAndLabor + taxAmount;

            txtTotalParts.Text = totalParts.ToString("F");
            txtTotalLabor.Text = totalLabor.ToString("F");
            txtTaxAmount.Text = taxAmount.ToString("F");
            txtTotalOrder.Text = totalOrder.ToString("F");
        }
    }
}

Return to the form
On the form, click FILE and double-click New Repair Order

Implement its Click event as follows:

private void mnuFileNew_Click(object sender, EventArgs e)
{
    this.txtCustomerName.Text = "";
    this.txtAddress.Text = "";
    this.txtCity.Text = "";
    this.txtState.Text = "";
    this.txtZIPCode.Text = "";
    this.txtMake.Text = "";
    this.txtModel.Text = "";
    this.txtCarYear.Text = "";
    this.txtProblem.Text = "";

    this.txtPartName1.Text = "";
    this.txtUnitPrice1.Text = "0.00";
    this.txtQuantity1.Text = "0";
    this.txtSubTotal1.Text = "0.00";
    this.txtPartName2.Text = "";
    this.txtUnitPrice2.Text = "0.00";
    this.txtQuantity2.Text = "0";
    this.txtSubTotal2.Text = "0.00";
    this.txtPartName3.Text = "";
    this.txtUnitPrice3.Text = "0.00";
    this.txtQuantity3.Text = "0";
    this.txtSubTotal3.Text = "0.00";
    this.txtPartName4.Text = "";
    this.txtUnitPrice4.Text = "0.00";
    this.txtQuantity4.Text = "0";
    this.txtSubTotal4.Text = "0.00";
    this.txtPartName5.Text = "";
    this.txtUnitPrice5.Text = "0.00";
    this.txtQuantity5.Text = "0";
    this.txtSubTotal5.Text = "0.00";

    this.txtJobDescription1.Text = "";
    this.txtJobPrice1.Text = "0.00";
    this.txtJobDescription2.Text = "";
    this.txtJobPrice2.Text = "0.00";
    this.txtJobDescription3.Text = "";
    this.txtJobPrice3.Text = "0.00";
    this.txtJobDescription4.Text = "";
    this.txtJobPrice4.Text = "0.00";
    this.txtJobDescription5.Text = "";
    this.txtJobPrice5.Text = "0.00";

    this.txtTotalParts.Text = "0.00";
    this.txtTotalLabor.Text = "0.00";
    this.txtTaxRate.Text = "7.75";
    this.txtTaxAmount.Text = "0.00";
    this.txtTotalOrder.Text = "0.00";

    this.txtRecommendations.Text = "";
    this.txtCustomerName.Focus();
}

Return to the form and click the first text box under Unit Price
In the Properties window, click the Events button and double-click Leave

Call the Calculate() method as follows:

private void txtUnitPrice1_Leave(object sender, EventArgs e)
{
    Calculate();
}

Return to the form
Click each text box under Unit Price and, in the Events section of the Properties Windows, click Leave to select txtUnitPrice1_Leave
Click each text box under Qty and, in the Events section of the Properties Windows, click Leave to select txtUnitPrice1_Leave
Click each text box under Price (in the Jobs Performed section of the form) and, in the Events section of the Properties Windows, click Leave to select txtUnitPrice1_Leave
Click the Tax Rate text box and, in the Events section of the Properties Windows, click Leave to select txtUnitPrice1_Leave
From the Printing section of the Toolbox, click the PrintDocument button and click the form
While the print document control is still selected, in the Properties window, change its name to docPrint
On the bar under the form, double-click docPrint to generate its default event

Implement the PrintPage event as follows:

private void docPrint_PrintPage(object sender,
            System.Drawing.Printing.PrintPageEventArgs e)
{
            e.Graphics.DrawLine(new Pen(Color.Black, 2), 60, 90, 680, 90);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 60, 93, 680, 93);

            string strDisplay = "College Park Auto Repair";
            System.Drawing.Font fntString = new Font("Times New Roman", 28,
                FontStyle.Bold);
            e.Graphics.DrawString(strDisplay, fntString,
                Brushes.Black, 160, 100);

            strDisplay = "Customer Car Repair Order";
            fntString = new System.Drawing.Font("Times New Roman", 18,
                FontStyle.Bold);
            e.Graphics.DrawString(strDisplay, fntString,
                Brushes.Black, 220, 150);

            e.Graphics.DrawLine(new Pen(Color.Black, 1), 60, 184, 680, 184);
            e.Graphics.DrawLine(new Pen(Color.Black, 2), 60, 187, 680, 187);

            fntString = new System.Drawing.Font("Times New Roman", 12,
                FontStyle.Bold);
            e.Graphics.DrawString("Order Identification", fntString,
                Brushes.Black, 80, 200);

            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 250, 640, 250);

            fntString = new System.Drawing.Font("Times New Roman", 10,
                FontStyle.Bold);
            e.Graphics.DrawString("Customer Name:", fntString,
                Brushes.Black, 100, 260);
            fntString = new System.Drawing.Font("Times New Roman", 10,
                FontStyle.Regular);
            e.Graphics.DrawString(txtCustomerName.Text, fntString,
                Brushes.Black, 260, 260); ;

            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 280, 640, 280);

            fntString = new Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Address:", fntString,
                Brushes.Black, 100, 290);
            fntString = new Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtAddress.Text, fntString,
                Brushes.Black, 260, 290); ;

            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 310, 640, 310);

            fntString = new Font("Times New Roman", 10, FontStyle.Regular);
            string strAddress = txtCity.Text.ToString() + ", " +
                                txtState.Text + " " + txtZIPCode.Text;
            e.Graphics.DrawString(strAddress, fntString, Brushes.Black, 260, 320);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 340, 640, 340);

            fntString = new Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Car:", fntString, Brushes.Black, 100, 350);
            fntString = new Font("Times New Roman", 10, FontStyle.Regular);
            string strCar = txtMake.Text + ", " + txtModel.Text +
                            ", " + txtCarYear.Text;
            e.Graphics.DrawString(strCar, fntString, Brushes.Black, 260, 350);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 370, 640, 370);

            fntString = new Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Problem Description:", fntString,
                Brushes.Black, 100, 380);
            fntString = new Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtProblem.Text, fntString,
                                  Brushes.Black,
                                  new RectangleF(260, 380, 420, 380));
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 400, 640, 400);

            fntString = new System.Drawing.Font("Times New Roman", 12, FontStyle.Bold);
            e.Graphics.DrawString("Parts Used", fntString,
                Brushes.Black, 80, 430);

            e.Graphics.DrawLine(new Pen(Color.Black, 2), 80, 450, 680, 450);

            e.Graphics.DrawString("Parts Name", fntString,
                Brushes.Black, 100, 460);
            e.Graphics.DrawString("Unit Price", fntString,
                Brushes.Black, 420, 460);
            e.Graphics.DrawString("Qty", fntString,
                Brushes.Black, 520, 460);
            e.Graphics.DrawString("Sub-Total", fntString,
                Brushes.Black, 562, 460);

            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 480, 640, 480);

            fntString = new Font("Times New Roman", 10, FontStyle.Regular);
            StringFormat fmtString = new StringFormat();
            fmtString.Alignment = StringAlignment.Far;

            e.Graphics.DrawString(txtPartName1.Text, fntString,
                Brushes.Black, 100, 490);
            e.Graphics.DrawString(txtUnitPrice1.Text, fntString,
                Brushes.Black, 480, 490, fmtString);
            e.Graphics.DrawString(txtQuantity1.Text, fntString,
                Brushes.Black, 540, 490, fmtString);
            e.Graphics.DrawString(txtSubTotal1.Text, fntString,
                Brushes.Black, 630, 490, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1),
                100, 510, 640, 510);

            e.Graphics.DrawString(txtPartName2.Text, fntString,
                Brushes.Black, 100, 520);
            e.Graphics.DrawString(txtUnitPrice2.Text, fntString,
                Brushes.Black, 480, 520, fmtString);
            e.Graphics.DrawString(txtQuantity2.Text, fntString,
                Brushes.Black, 540, 520, fmtString);
            e.Graphics.DrawString(txtSubTotal2.Text, fntString,
                Brushes.Black, 630, 520, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 540, 640, 540);

            e.Graphics.DrawString(txtPartName3.Text, fntString,
                Brushes.Black, 100, 550);
            e.Graphics.DrawString(txtUnitPrice3.Text, fntString,
                Brushes.Black, 480, 550, fmtString);
            e.Graphics.DrawString(txtQuantity3.Text, fntString,
                Brushes.Black, 540, 550, fmtString);
            e.Graphics.DrawString(txtSubTotal3.Text, fntString,
                Brushes.Black, 630, 550, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1),
                100, 570, 640, 570);

            e.Graphics.DrawString(txtPartName4.Text, fntString,
                Brushes.Black, 100, 580);
            e.Graphics.DrawString(txtUnitPrice4.Text, fntString,
                Brushes.Black, 480, 580, fmtString);
            e.Graphics.DrawString(txtQuantity4.Text, fntString,
                Brushes.Black, 540, 580, fmtString);
            e.Graphics.DrawString(txtSubTotal4.Text, fntString,
                Brushes.Black, 630, 580, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 600, 640, 600);

            e.Graphics.DrawString(txtPartName5.Text, fntString,
                Brushes.Black, 100, 610);
            e.Graphics.DrawString(txtUnitPrice5.Text, fntString,
                Brushes.Black, 480, 610, fmtString);
            e.Graphics.DrawString(txtQuantity5.Text, fntString,
                Brushes.Black, 540, 610, fmtString);
            e.Graphics.DrawString(txtSubTotal5.Text, fntString,
                Brushes.Black, 630, 610, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 630, 640, 630);

            fntString = new Font("Times New Roman", 12, FontStyle.Bold);
            e.Graphics.DrawString("Jobs Performed", fntString,
                Brushes.Black, 80, 650);
            e.Graphics.DrawLine(new Pen(Color.Black, 2), 80, 670, 680, 670);

            e.Graphics.DrawString("Job Name", fntString, Brushes.Black, 100, 680);
            e.Graphics.DrawString("Price", fntString, Brushes.Black, 562, 680);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 700, 640, 700);

            fntString = new Font("Times New Roman", 10, FontStyle.Regular);

            e.Graphics.DrawString(txtJobDescription1.Text, fntString,
                Brushes.Black, 100, 710);
            e.Graphics.DrawString(txtJobPrice1.Text, fntString,
                Brushes.Black, 600, 710, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 730, 640, 730);

            e.Graphics.DrawString(txtJobDescription2.Text, fntString,
                Brushes.Black, 100, 740);
            e.Graphics.DrawString(txtJobPrice2.Text, fntString,
                Brushes.Black, 600, 740, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 760, 640, 760);

            e.Graphics.DrawString(txtJobDescription3.Text, fntString,
                Brushes.Black, 100, 770);
            e.Graphics.DrawString(txtJobPrice3.Text, fntString,
                Brushes.Black, 600, 770, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 790, 640, 790);

            e.Graphics.DrawString(txtJobDescription4.Text, fntString,
                Brushes.Black, 100, 800);
            e.Graphics.DrawString(txtJobPrice4.Text, fntString,
                Brushes.Black, 600, 800, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 820, 640, 820);

            e.Graphics.DrawString(txtJobDescription5.Text, fntString,
                Brushes.Black, 100, 830);
            e.Graphics.DrawString(txtJobPrice5.Text, fntString,
                Brushes.Black, 600, 830, fmtString);
            e.Graphics.DrawLine(new Pen(Color.Black, 1), 100, 850, 640, 850);

            fntString = new System.Drawing.Font("Times New Roman", 12, FontStyle.Bold);
            e.Graphics.DrawString("Order Summary", fntString,
                Brushes.Black, 80, 870);
            e.Graphics.DrawLine(new Pen(Color.Black, 2), 80, 890, 680, 890);

            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Total Parts:", fntString,
                Brushes.Black, 500, 900);
            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtTotalParts.Text, fntString,
                Brushes.Black, 640, 900, fmtString);

            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Total Labor:", fntString,
                Brushes.Black, 500, 920);
            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtTotalLabor.Text, fntString,
                Brushes.Black, 640, 920, fmtString);

            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Tax Rate:", fntString,
                Brushes.Black, 500, 940);
            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtTaxRate.Text, fntString,
                Brushes.Black, 640, 940, fmtString);

            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Tax Amount:", fntString,
                Brushes.Black, 500, 960);
            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtTaxAmount.Text, fntString,
                Brushes.Black, 640, 960, fmtString);

            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Repair Total:", fntString,
                Brushes.Black, 500, 980);
            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtTotalOrder.Text, fntString,
                Brushes.Black, 640, 980, fmtString);

            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Bold);
            e.Graphics.DrawString("Recommendations:", fntString,
                Brushes.Black, 100, 900);
            fntString = new System.Drawing.Font("Times New Roman", 10, FontStyle.Regular);
            e.Graphics.DrawString(txtRecommendations.Text, fntString,
                Brushes.Black, new RectangleF(100, 920, 350, 280));
}

Return to the form
From the Printing section of the Toolbox, click the PrintDialog button and click the form
While the print control is still selected, in the Properties window, change its Name to dlgPrint
Click Document and select docPrint
On the form, click FILE and double-click Print

Implement its Click event as follows:

private void mnuFilePrint_Click(object sender, EventArgs e)
{
    if ( dlgPrint.ShowDialog() == DialogResult.OK)
    {
        docPrint.Print();
    }
}

Return to the form
From the Printing section of the Toolbox, click PrintPreviewDialog and click the form
In the Properties window, change its (Name) to dlgPrintPreview
Still in the Properties windows, set its Document property to docPrint
On the form, click FILE and double-click the Print Preview

Implement the event as follows:

private void mnuFilePrintPreview_Click(object sender, EventArgs e)
{
    dlgPrintPreview.ShowDialog();
}

Save the file

The XML Text Writer Fundamentals

Besides the XmlDocument and the derived classes of XmlNode, the .NET Framework provides the XmlTextWriter class, which is derived from XmlWriter. The XmlTextWriter class works in a top-down approach to create, or deal with, the contents of an XML file. This class writes an XML node and moves down without referring back:

This means that, once you have created a node using the XmlTextWriter, you have no way of referring back to it.

To use an XmlTextWriter object, first declare a variable of the type of this class and initialize it using one of its three constructors.

If you had already created a Stream-based object such as declaring a variable of type FileStream but you didn't define an encoding scheme, you can pass the Stream-based object to an XmlTextWriter but you must take this time to specify the encoding scheme. To support this concept, the XmlTextWriter provides a constructor with the following syntax:

public XmlTextWriter(Stream w,  Encoding encoding);

The first argument of this constructor can be a Stream-derived variable. The second argument specifies the encoding scheme that would be applied. The default is UTF-8. Based on this, if you want to use the UTF-8 encoding scheme, you can pass it or pass the argument as 0. If you want to use another encoding scheme, pass it to the constructor.

To work from scratch, that is, to initiate a file with manually-created nodes, you can pass the desired name of the file to the XmlTextWriter constructor using the following syntax:

public XmlTextWriter(string filename, Encoding encoding);

In this case, you must provide the name of, or path to, the file, whose content you are creating, as the first argument. You must pass the desired encoding scheme as the second argument. Here is an example:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Xml;

namespace SchoolRegistration
{
    public partial class Exercise : Form
    {
        public Exercise()
        {
            InitializeComponent();
        }

        private void btnDocument_Click(object sender, EventArgs e)
        {
            XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                           Encoding.UTF8);
        }
    }
}

Eventually, when you have finished using the XmlTextWriter object, you must free the memory it was using by calling the XmlTextWriter.Flush() method. To release the resources that the object was using, call the XmlTextWriter.Close() method. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                   Encoding.UTF8);

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

Creating the XML Declaration

Declaring an XmlTextWriter variable allows you to indicate that you intend to create a new XML file. With the variable ready, you can start writing the file's content. As mentioned in previous lessons, an XML file starts at the top with an XML declaration. To create this declaration, you can call the XmlTextWriter.WriteStartDocument() method. This method is overloaded with two versions. The syntax of one of them is:

public void WriteStartDocument();

This method creates a declaration, sets the XML version to 1.0, and includes the encoding scheme you specified in the constructor. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                   Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

To } an XML file, you must close its declaration. This is done by calling the XmlTextWriter.WriteEndDocument() method. Its syntax is:

public void WriteEndDocument();

This method indicates that the XML file has ended and allows the compiler to stop reading it down. This would be done as follows:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                    Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    xmlTxtWriter.WriteEndDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

Creating the Root Element

Between the XML declaration and the end of the file, that is, between the call to XmlTextWriter.WriteStartDocument() and the call to XmlTextWriter.WriteEndDocument() methods, you can create the necessary nodes of the file. As reviewed in previous lessons, the most regular node of an XML file is the element. To create an element, the XmlTextWriter class provides the WriteStartElement() method that is overloaded with various versions. One of the versions of this method and that is inherited from the XmlWriter class uses the following syntax:

public void WriteStartElement(string localName);

This method takes as argument the name of the element that will be created. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                    Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    xmlTxtWriter.WriteStartElement("students");

    xmlTxtWriter.WriteEndDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

As you may know from XML, every element must be closed. To close an XML element, call the XmlTextWriter.WriteEndElement() method. Its syntax is:

public override void WriteEndElement();

When calling this method, always make sure that you know the element it is closing, which must correspond to an appropriate previous call to a WriteStartElement() method. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                    Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    xmlTxtWriter.WriteStartElement("students");
    xmlTxtWriter.WriteEndElement();

    xmlTxtWriter.WriteEndDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

This would produce:

As you can see from the result, a single or the first call to the WriteStartElement() method creates the root element that is required for every XML file. This means that, after this (first) call but before its corresponding WriteEndElement() call, you can create the necessary nodes that you want to include as part of the file.

Creating the Child Elements of the Root

To help you create child elements of the root node, you can keep calling the XmlTextWriter.WriteStartElement() method as necessary and appropriately closing it. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                    Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    xmlTxtWriter.WriteStartElement("students");
    xmlTxtWriter.WriteStartElement("student");

    xmlTxtWriter.WriteEndElement();
    xmlTxtWriter.WriteEndElement();

    xmlTxtWriter.WriteEndDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

If you simply call this method as done above, the element would be empty. Based on this, the above code would produce:

If you want the element to have a value, call the XmlTextWriter.WriteString() method. Its syntax is:

public void WriteString(string text);

This method must immediately follow the call to WriteStartElement() that creates a new element. It takes as argument the value for the immediately previously defined element. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                    Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    xmlTxtWriter.WriteStartElement("students");

    xmlTxtWriter.WriteStartElement("student");
    xmlTxtWriter.WriteString("Raymond Sanson");
    xmlTxtWriter.WriteEndElement();

    xmlTxtWriter.WriteEndDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

This would produce:

If you call the XmlTextWriter.WriteStartElement() method and you want the element to have a value, remember to call the XmlTextWriter.WriteString() method, and then call the XmlTextWriter.WriteEndElement() method. An alternative is to call the XmlWriter.WriteElementString() method that comes in two versions. The syntax of one of these versions is:

public void WriteElementString(string localName, string value);

The first argument to this method is the name of the element that will be created. The second argument is the value of the element. This method creates and closes its element. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                    Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    xmlTxtWriter.WriteStartElement("students");

    xmlTxtWriter.WriteStartElement("student");
    xmlTxtWriter.WriteString("Raymond Sanson");
    xmlTxtWriter.WriteEndElement();

    xmlTxtWriter.WriteElementString("student", "Brigitte Arano");
    xmlTxtWriter.WriteEndElement();

    xmlTxtWriter.WriteEndDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

This would produce:

In the same way, you can create the necessary elements and their child elements as necessary. Be careful to appropriately start an element and remember to close it if necessary. Here are examples:

private void btnDocument_Click(object sender, EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
                                                    Encoding.UTF8);

    xmlTxtWriter.WriteStartDocument();

    // Create the root element named students
    xmlTxtWriter.WriteStartElement("students");

    // Start a child element named student
    xmlTxtWriter.WriteStartElement("student");

    // Create a number for the student
    xmlTxtWriter.WriteStartElement("studentnumber");
    xmlTxtWriter.WriteString("740597");
    xmlTxtWriter.WriteEndElement();

    // Create a name for the student
    xmlTxtWriter.WriteStartElement("fullname");
    xmlTxtWriter.WriteString("Christie Aronson");
    xmlTxtWriter.WriteEndElement();

    // Create a date of birth for the student
    xmlTxtWriter.WriteStartElement("dateofbirth");
    xmlTxtWriter.WriteString("02/16/1988");
    xmlTxtWriter.WriteEndElement();

    // Create a Format child element to the Video element
    xmlTxtWriter.WriteStartElement("Gender");
    xmlTxtWriter.WriteString("Female");
    xmlTxtWriter.WriteEndElement();

    // Close the student node
    xmlTxtWriter.WriteEndElement();

    // Start a new student element
    xmlTxtWriter.WriteStartElement("student");

    // Create the child elements of the new student element
    xmlTxtWriter.WriteElementString("studentnumber", "249575");
    xmlTxtWriter.WriteElementString("fullname", "Julius Raymonds");
    xmlTxtWriter.WriteElementString("dateofbirth", "12/07/1992");
    xmlTxtWriter.WriteElementString("Gender", "Male");
    // The current student node
    xmlTxtWriter.WriteEndElement();

    // Close the root element
    xmlTxtWriter.WriteEndElement();

    xmlTxtWriter.WriteEndDocument();

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

This would produce:

Practical Learning: Creating the Elements of an XML File

From the Dialogs section of the Toolbox, click SaveFileDialog and click the form
Change its properties as follows:
Title: Save Current Repair Order
DefaultExt: xml
Filter: Repair Orders (*.xml)|*.xml|All Files|
Name: dlgSave
On the form, click FILE and double-click Save Current Order

To create the XML file with the desired elements, implement the event as follows:

private void mnuFileSave_Click(object sender, EventArgs e)
{
    // Just in case, calculate the order now
    Calculate();
    // This number will be used to incrementally
    // create the files by their names
    int iFilename;
    string strFilename;
    
    // If this directory doesn't exist, create it
    // Also, get a reference to this directory for later use
    string strDirectory = @"C:\College Park Auto Repair";
    DirectoryInfo dirInfo =
                Directory.CreateDirectory(strDirectory);

    // Get the list of files, if any, from the above folder
    FileInfo[] fleList = dirInfo.GetFiles("*.xml");

    // If there is no XML file in the directory,
    // then get ready to create the first file
    if (fleList.Length == 0)
    {
        // Create the name of the (initial) file
        iFilename = 1000;
    }
    else // If there was at least one file in the directory
    {
                // Get a reference to the last file
                FileInfo fleLast = fleList[fleList.Length - 1];
                // Get the name of the last file without its extension
                string fwe = Path.GetFileNameWithoutExtension(fleLast.FullName);
                // Get the name of the file
                iFilename = int.Parse(fwe);
            }

            strFilename = strDirectory + "\\" + (iFilename + 1).ToString() + ".xml";
                
            // Get ready to display it in the Save dialog box
            dlgSave.FileName = strFilename;

            // Find out if the user clicked OK after displaying the Save dialog box
            if (dlgSave.ShowDialog() == DialogResult.OK)
            {
                XmlTextWriter wtrRepairOrder = new XmlTextWriter(strFilename,
                    Encoding.UTF8);
                wtrRepairOrder.Formatting = Formatting.Indented;
                wtrRepairOrder.Indentation = 4;

                // Create the contents of the XML file
                // Notice that we are not making an attempt to check the values
                wtrRepairOrder.WriteStartDocument();

                wtrRepairOrder.WriteStartElement("RepairOrders");
                wtrRepairOrder.WriteStartElement("Invoice");

                wtrRepairOrder.WriteElementString("CustomerName", this.txtCustomerName.Text);
                wtrRepairOrder.WriteElementString("Addres", this.txtAddress.Text);
                wtrRepairOrder.WriteElementString("City", this.txtCity.Text);
                wtrRepairOrder.WriteElementString("State", this.txtState.Text);
                wtrRepairOrder.WriteElementString("ZIPCode", this.txtZIPCode.Text);
                wtrRepairOrder.WriteElementString("Make", this.txtMake.Text);
                wtrRepairOrder.WriteElementString("Model", this.txtModel.Text);
                wtrRepairOrder.WriteElementString("CarYear", this.txtCarYear.Text);
                wtrRepairOrder.WriteElementString("ProbDescription", this.txtProblem.Text);
                wtrRepairOrder.WriteElementString("PartName1", this.txtPartName1.Text);
                wtrRepairOrder.WriteElementString("UnitPrice1", this.txtUnitPrice1.Text);
                wtrRepairOrder.WriteElementString("Quantity1", this.txtQuantity1.Text);
                wtrRepairOrder.WriteElementString("SubTotal1", this.txtSubTotal1.Text);
                wtrRepairOrder.WriteElementString("PartName2", this.txtPartName2.Text);
                wtrRepairOrder.WriteElementString("UnitPrice2", this.txtUnitPrice2.Text);
                wtrRepairOrder.WriteElementString("Quantity2", this.txtQuantity2.Text);
                wtrRepairOrder.WriteElementString("SubTotal2", this.txtSubTotal2.Text);
                wtrRepairOrder.WriteElementString("PartName3", this.txtPartName3.Text);
                wtrRepairOrder.WriteElementString("UnitPrice3", this.txtUnitPrice3.Text);
                wtrRepairOrder.WriteElementString("Quantity3", this.txtQuantity3.Text);
                wtrRepairOrder.WriteElementString("SubTotal3", this.txtSubTotal3.Text);
                wtrRepairOrder.WriteElementString("PartName4", this.txtPartName4.Text);
                wtrRepairOrder.WriteElementString("UnitPrice4", this.txtUnitPrice4.Text);
                wtrRepairOrder.WriteElementString("Quantity4", this.txtQuantity4.Text);
                wtrRepairOrder.WriteElementString("SubTotal4", this.txtSubTotal4.Text);
                wtrRepairOrder.WriteElementString("PartName5", this.txtPartName5.Text);
                wtrRepairOrder.WriteElementString("UnitPrice5", this.txtUnitPrice5.Text);
                wtrRepairOrder.WriteElementString("Quantity5", this.txtQuantity5.Text);
                wtrRepairOrder.WriteElementString("SubTotal5", this.txtSubTotal5.Text);
                wtrRepairOrder.WriteElementString("JobDescription1", this.txtJobDescription1.Text);
                wtrRepairOrder.WriteElementString("JobPrice1", this.txtJobPrice1.Text);
                wtrRepairOrder.WriteElementString("JobDescription2", this.txtJobDescription2.Text);
                wtrRepairOrder.WriteElementString("JobPrice2", this.txtJobPrice2.Text);
                wtrRepairOrder.WriteElementString("JobDescription3", this.txtJobDescription3.Text);
                wtrRepairOrder.WriteElementString("JobPrice3", this.txtJobPrice3.Text);
                wtrRepairOrder.WriteElementString("JobDescription4", this.txtJobDescription4.Text);
                wtrRepairOrder.WriteElementString("JobPrice4", this.txtJobPrice4.Text);
                wtrRepairOrder.WriteElementString("JobDescription5", this.txtJobDescription5.Text);
                wtrRepairOrder.WriteElementString("JobPrice5", this.txtJobPrice5.Text);
                wtrRepairOrder.WriteElementString("TotalPart", this.txtTotalParts.Text);
                wtrRepairOrder.WriteElementString("TotalLabor", this.txtTotalLabor.Text);
                wtrRepairOrder.WriteElementString("TaxRate", this.txtTaxRate.Text);
                wtrRepairOrder.WriteElementString("TaxAmount", this.txtTaxAmount.Text);
                wtrRepairOrder.WriteElementString("TotalOrder", this.txtTotalOrder.Text);
                wtrRepairOrder.WriteElementString("Recommendation", this.txtRecommendations.Text);

                wtrRepairOrder.WriteEndElement();
                wtrRepairOrder.WriteEndElement();

                wtrRepairOrder.WriteEndDocument();

                wtrRepairOrder.Flush();
                wtrRepairOrder.Close();
    }
}

Execute the application to test it
Create a new record and click Calculate Order:
Click File -> Save and OK to Save the file
Click File -> New Repair Order
Create another repair order:
Save it
Close the form and return to your programming environment

Saving a File As XML

If you are creating a text-intensive document and you want to save it as an XML file, for example if you have declared a variable of type TextWriter-derived class (such as StringWriter or StreamWriter), you can use that file to initialize the XmlTextWriter variable. To support TextWriter documents, the XmlTextWriter provides a constructor with the following syntax:

public XmlTextWriter(TextWriter w);

This constructor expects as argument TextWriter-based object. This means that you should have defined the TextWriter object prior to passing it to this constructor. This also implies that the TextWriter was used to specify the encoding scheme that would be used. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    string strFilename = "students.xml";

    FileStream fleStream = new FileStream("students.xml",
                      FileMode.Create,
                      FileAccess.Write,
                      FileShare.None);
    StreamWriter stmWriter = new StreamWriter(fleStream);
    XmlTextWriter xmlTxtWriter = new XmlTextWriter(stmWriter);

    stmWriter.Flush();
    stmWriter.Close();
}

To actually write the contents of the document, you can create each paragraph by calling the XmlTextWriter.WriteStartElement() method the same way we did earlier. Here is an example:

private void btnDocument_Click(object sender, EventArgs e)
{
    string strFilename = "students.xml";

    FileStream fleStream = new FileStream("memo.xml",
                      FileMode.Create,
                      FileAccess.Write,
                      FileShare.None);
    StreamWriter stmWriter = new StreamWriter(fleStream);
    XmlTextWriter xmlTxtWriter = new XmlTextWriter(stmWriter);
    
    xmlTxtWriter.WriteStartDocument();
    xmlTxtWriter.WriteStartElement("ToAllEmployees");

    for (int i = 0; i < txtEditor.Lines.Length; i++)
    {
        xmlTxtWriter.WriteStartElement("Notice");
        xmlTxtWriter.WriteString(this.txtEditor.Lines[i].ToString());
        xmlTxtWriter.WriteEndElement();
    }

    xmlTxtWriter.WriteEndDocument();

    stmWriter.Flush();
    stmWriter.Close();
}

Reading From an XML File

Introduction

Once an XML file exists, you can read it to retrieve the values of its nodes. To support opening an XML file and reading its contents, the .NET Framework provides the XmlTextReader class that is derived from the XmlReader class. The XmlTextReader class is equipped with all the necessary properties and methods to explore the contents of an XML file.

Like XmlTextWriter, the XmlTextReader class reads a file from top to bottom without going back up once it has passed a node:

This means that, when using the XmlTextReader class to read an XML file, once you have read a node and moved down the file, you cannot refer back to the previous node and you cannot access a previous node: once you have passed a node, you cannot access it anymore.

Using and XML Text Reader

To use an XML text reader, declare a variable of type XmlTextReader and initialize it with one of its constructors. This class is equipped with 14 constructors. If you want to open a file whose name or path you know, use the following constructor:

public XmlTextReader(string url);

This constructor takes as argument the name of, or path to, an XML file. If the file is found, it would be opened. If the file doesn't exist or there is an error in the string that specifies its path, the compiler would throw an XmlException exception.

Reading Nodes

After declaring an XmlTextReader variable, you can start reading the content of the file. To support this, you can call the XmlTextReader.Read() method. Its syntax is:

public override bool Read();

As mentioned previously, the file is read from top to bottom. Based on this, when you call the Read() method, it reads the first node, moves to the next, and so on until it reaches the end of the file. While reading the file, every time this method reaches a node, you can find out what type of node it is by checking the XmlTextReader.NodeType property. This can help you take a specific action if the reached node meets a certain criterion.

As reviewed in our introductions to XML, each node has a name and possibly a value. You can find out the name of a node by checking the XmlTextReader.Name property. To know the value of a node, retrieve its XmlTextReader.Value property.

Practical Learning: Reading the Elements of an XML File

Display the form.
From the Dialogs section of the Toolbox, click OpenFileDialog and click the form
Change its properties as follows:
Title: Open Existing Repair Order
DefaultExt: xml
Filter: Repair Orders (*.xml)|*.xml|All Files|
Name: dlgOpen
On the form, click FILE and double-click Open Existing Order

Implement the Click event as follows:

private void mnuFileOpen_Click(object sender, EventArgs e)
{
    XmlTextReader rdrRepairOrder = null;

    try
    {
        if( dlgOpen.ShowDialog() == DialogResult.OK )
        {
            rdrRepairOrder = new XmlTextReader(dlgOpen.FileName);

            // Scan the XML file
            while( rdrRepairOrder.Read() )
            {
                // every time you find an element, find out what type it is
                // If you find text, put it in the combo box' list
                if( (XmlNodeType.Element != 0) &&
		    (rdrRepairOrder.Name == "CustomerName") )
                {
                    txtCustomerName.Text = rdrRepairOrder.ReadElementString("CustomerName");
                    txtAddress.Text = rdrRepairOrder.ReadElementString("Addres");
                    txtCity.Text = rdrRepairOrder.ReadElementString("City");
                    txtState.Text = rdrRepairOrder.ReadElementString("State");
                    txtZIPCode.Text = rdrRepairOrder.ReadElementString("ZIPCode");
                    txtMake.Text = rdrRepairOrder.ReadElementString("Make");
                    txtModel.Text = rdrRepairOrder.ReadElementString("Model");
                    txtCarYear.Text = rdrRepairOrder.ReadElementString("CarYear");
                    txtProblem.Text = rdrRepairOrder.ReadElementString("ProbDescription");
                    txtPartName1.Text = rdrRepairOrder.ReadElementString("PartName1");
                    txtUnitPrice1.Text = rdrRepairOrder.ReadElementString("UnitPrice1");
                    txtQuantity1.Text = rdrRepairOrder.ReadElementString("Quantity1");
                    txtSubTotal1.Text = rdrRepairOrder.ReadElementString("SubTotal1");
                    txtPartName2.Text = rdrRepairOrder.ReadElementString("PartName2");
                    txtUnitPrice2.Text = rdrRepairOrder.ReadElementString("UnitPrice2");
                    txtQuantity2.Text = rdrRepairOrder.ReadElementString("Quantity2");
                    txtSubTotal2.Text = rdrRepairOrder.ReadElementString("SubTotal2");
                    txtPartName3.Text = rdrRepairOrder.ReadElementString("PartName3");
                    txtUnitPrice3.Text = rdrRepairOrder.ReadElementString("UnitPrice3");
                    txtQuantity3.Text = rdrRepairOrder.ReadElementString("Quantity3");
                    txtSubTotal3.Text = rdrRepairOrder.ReadElementString("SubTotal3");
                    txtPartName4.Text = rdrRepairOrder.ReadElementString("PartName4");
                    txtUnitPrice4.Text = rdrRepairOrder.ReadElementString("UnitPrice4");
                    txtQuantity4.Text = rdrRepairOrder.ReadElementString("Quantity4");
                    txtSubTotal4.Text = rdrRepairOrder.ReadElementString("SubTotal4");
                    txtPartName5.Text = rdrRepairOrder.ReadElementString("PartName5");
                    txtUnitPrice5.Text = rdrRepairOrder.ReadElementString("UnitPrice5");
                    txtQuantity5.Text = rdrRepairOrder.ReadElementString("Quantity5");
                    txtSubTotal5.Text = rdrRepairOrder.ReadElementString("SubTotal5");
                    txtJobDescription1.Text = rdrRepairOrder.ReadElementString("JobDescription1");
                    txtJobPrice1.Text = rdrRepairOrder.ReadElementString("JobPrice1");
                    txtJobDescription2.Text = rdrRepairOrder.ReadElementString("JobDescription2");
                    txtJobPrice2.Text = rdrRepairOrder.ReadElementString("JobPrice2");
                    txtJobDescription3.Text = rdrRepairOrder.ReadElementString("JobDescription3");
                    txtJobPrice3.Text = rdrRepairOrder.ReadElementString("JobPrice3");
                    txtJobDescription4.Text = rdrRepairOrder.ReadElementString("JobDescription4");
                    txtJobPrice4.Text = rdrRepairOrder.ReadElementString("JobPrice4");
                    txtJobDescription5.Text = rdrRepairOrder.ReadElementString("JobDescription5");
                    txtJobPrice5.Text = rdrRepairOrder.ReadElementString("JobPrice5");
                    txtTotalParts.Text = rdrRepairOrder.ReadElementString("TotalPart");
                    txtTotalLabor.Text = rdrRepairOrder.ReadElementString("TotalLabor");
                    txtTaxRate.Text = rdrRepairOrder.ReadElementString("TaxRate");
                    txtTaxAmount.Text = rdrRepairOrder.ReadElementString("TaxAmount");
                    txtTotalOrder.Text = rdrRepairOrder.ReadElementString("TotalOrder");
                    txtRecommendations.Text = rdrRepairOrder.ReadElementString("Recommendation");
                }
            }
        }
    }
    catch (XmlException)
    {
        MessageBox.Show("The file name you provided is not valid");
    }
    finally
    {
        rdrRepairOrder.Close();
    }
}

Execute the application and open one the previous orders

Details on XML Reading and Writing

Indentation

Consider a valid XML file such as the following, opened in Notepad:

If you were asked to examine this file, you can see that its crowded words make it difficult to read. To include a white space when writing to the file, you can call the XmlTextWriter.WriteWhiteSpace() method. Its syntax is:

public override void WriteWhitespace(string ws);

Besides white spaces, indentation consists of setting empty spaces on the left of child nodes to make the file easier to read. Based on this, indentation is not a requirement but a convenience. While the WriteWhiteSpace() method allows you to explicitly create a white space in the file, the XmlTextWriter class is equipped with the Formatting property. This property is a value of the Formatting enumeration. The Formatting enumeration has two members. The Indented value ensures that each child node would be indented from its parent.

If you manually create an XML file, whether using Notepad, Visual Studio, or another text editor, you can indent the nodes as you see fit. To let the compiler know that you want the nodes to be indented, assign the Formatting.Indented member to its Formatting property. Here is an example:

void BtnSaveClick(System.object sender, System.EventArgs e)
{
    XmlTextWriter xmlTxtWriter = new XmlTextWriter("students.xml",
						   Encoding.UTF8);
    xmlTxtWriter.Formatting = Formatting.Indented;

    xmlTxtWriter.Flush();
    xmlTxtWriter.Close();
}

If you manually create an XML file, you can specify the number of empty spaces on the left of a node by pressing the Space bar a few times before typing the node. Most people use 2 or 4 characters for the indentation. If you are programmatically creating the file, to specify the number of characters that should be used during indentation, assign the desired integer to the XmlTextWriter.Indentation property. If you don't use this property, the compiler would use two characters. You can also find out the number of characters used for indentation by retrieving the value of this property.

As mentioned above, indentation consists of entering white spaces on the left of child nodes. Instead of empty spaces, if you want to use another character, assign it to the XmlTextWriter.IndentChar property.

Practical Learning: Indenting XML Nodes

Display the Central.cs file and, in the Members combo box, select mnuFileSave_Click(object sender, EventArgs e)

To control the indentation when the file is saved, change the top section of the event as follows:

private void mnuFileSave_Click(object sender, EventArgs e)
{
    . . . No Change

    // Find out if the user clicked OK after displaying the Save dialog box
    if (dlgSave.ShowDialog() == DialogResult.OK)
    {
        XmlTextWriter wtrRepairOrder = new XmlTextWriter(strFilename,
                    Encoding.UTF8);
        wtrRepairOrder.Formatting = Formatting.Indented;
        wtrRepairOrder.Indentation = 4;

    }

    . . . No Change
}

Return to the form
Click File and double-click Exit

Implement it as follows:

private void mnuFileExit_Click(object sender, EventArgs e)
{
    Close();
}

Execute the application
Create and save a few more repair orders
Close the form