ADO.NET Data Selection: Details on Data Selection: Sorting the Records

	Details on Data Selection: Sorting the Records

Sorting the Records in the Table Window

The lists of records we get with a SELECT statement are presented in the order they have in the table. SQL allows you to arrange records in alphabetical order, in chronological order or in numeric incremental order. After selecting a series of columns, you may want to list the records following an alphabetical order from one specific field. To get an alphabetical or an incremental order of records, you must let the database know what field would be used as reference.

To specify the order, if you are using a table window in Microsoft SQL Server Management Studio or in Microsoft Visual Studio:

In the Diagram section, you can right-click a field and select either Sort Ascending or Sort Descending

In the Criteria section of the window, under the Sort Type column, click the corresponding box of the desired column. This would reveal that it is a combo box. Then click the arrow of that combo box and make your selection between Ascending and Descending:

Using the Table Window

If you select Ascending or Sort Ascending, the list of records would be re-arranged based on the type of the selected column:

If the column is text-based (char, varchar, and their variants), the records would be arranged in alphabetical order
If the column is date or time-based (datetime or smalldatetime), the records would be arranged in chronological order
If the column is number-based, the records would be arranged in incremental order
If the column is Boolean-based (bit), the FALSE records would appear first

If you select Descending or Sort Descending, the list of records would be re-arranged based on the type of the selected column:

If the column is text-based (char, varchar, and their variants), the records would be arranged in reverse alphabetical order
If the column is date or time-based (datetime or smalldatetime), the records would be arranged in reverse chronological order
If the column is number-based, the records would be arranged in decremental order
If the column is Boolean-based (bit), the TRUE records would appear first

After selecting the desired Sort Type, you can execute the SQL statement.

Practical Learning: Introducing Data Sorting

Start Microsoft Visual C# and create a new Windows Application named AltairRealtors6
In the Solution Explorer, right-click Form1.cs and click Rename
Type AltairRealtors.cs and press Enter

Double-click the middle of the form and implement the Load event as follows:

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

namespace AltairRealtors6
{
    public partial class AltairRealtors : Form
    {
	public AltairRealtors()
	{
	    InitializeComponent();
	}

	private void AltairRealtors_Load(object sender, EventArgs e)
	{
	    using (SqlConnection cnnAltairRealtors1 =
		new SqlConnection("Data Source=(local);" +
		"Integrated Security='SSPI';"))
	    {
		string strDatabase = "IF EXISTS (" +
			"SELECT * " +
			" FROM sys.databases " +
			" WHERE name = N'AltairRealtors1' " +
			")" +
			"DROP DATABASE AltairRealtors1;" +
			"CREATE DATABASE AltairRealtors1;";

		SqlCommand cmdAltairRealtors1 = new SqlCommand(strDatabase,
		cnnAltairRealtors1);

		cnnAltairRealtors1.Open();
		cmdAltairRealtors1.ExecuteNonQuery();

	MessageBox.Show("The AltairRealtors1 database has been created");
	    }

	    using (SqlConnection cnnAltairRealtors1 =
		new SqlConnection("Data Source=(local);" +
		"Database='AltairRealtors1';" +
		"Integrated Security='SSPI';"))
	    {
		string strAltairRealtors1 =
			"CREATE TABLE Properties" +
			"(" +
			"PropertyID int identity(1,1) NOT NULL," +
			"PropertyNumber char(6)," +
			"Address varchar(100)," +
			"City varchar(50)," +
			"State char(2)," +
			"ZIPCode varchar(12)," +
			"PropertyType varchar(40)," +
			"Condition varchar(32)," +
			"Bedrooms smallint," +
			"Bathrooms float," +
			"FinishedBasement bit," +
			"IndoorGarage bit," +
			"Stories smallint," +
			"YearBuilt smallint," +
			"MarketValue money" +
	        ");";

	        SqlCommand cmdAltairRealtors1 =
			new SqlCommand(strAltairRealtors1,
			cnnAltairRealtors1);

	        cnnAltairRealtors1.Open();
	        cmdAltairRealtors1.ExecuteNonQuery();

	        MessageBox.Show("The Properties table has been created");
	    }

	    using (SqlConnection cnnAltairRealtors1 =
		new SqlConnection("Data Source=(local);" +
			"Database='AltairRealtors1';" +
			"Integrated Security='SSPI';"))
	    {
		string strAltairRealtors1 =
	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('524880', '1640 Lombardo Ave', 'Silver Spring', 'MD'," +
"'20904', 'Single Family', 'Good', 4, 2.5, 3, 1, 3, 1995, 495880.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('688364', '10315 North Hacht Rd', 'College Park', 'MD'," +
		"'20747', 'Single Family', 'Excellent', 4, 3.5, 3," +
		"1, 2, 2000, 620724.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, FinishedBasement," +
		"Stories, MarketValue)" +
		"VALUES('611464', '6366 Lolita Drive', 'Laurel', 'MD'," +
		"'20707', 'Single Family', 'Good', 1, 2, 422625.00);" +

		"INSERT INTO Properties(Address, City, PropertyType," +
		"Bedrooms, MarketValue)" +
		"VALUES('9002 Palasko Hwy', 'Tysons Corner'," +
		"'Condominium', 2, 422895.00);" +

		"INSERT INTO Properties(PropertyNumber, State," +
		"ZIPCode, Bedrooms, YearBuilt, MarketValue)" +
		"VALUES('420115', 'DC'," +
		"'20011', 2, 1982, 312555);" +

		"INSERT INTO Properties(PropertyNumber, City, ZIPCode," +
		"PropertyType, Bedrooms, YearBuilt, MarketValue)" +
		"VALUES('917203', 'Alexandria', '22024'," +
		"'Single Family', 3, 1965, 345660.00);" +

 	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
	"PropertyType, Condition, Bedrooms, Bathrooms, MarketValue)" +
		"VALUES('200417', '4140 Holisto Crt', 'Germantown', 'MD'," +
		"'Condominium', 'Excellent', 2, 1, 215495.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('927474', '9522 Lockwood Rd', 'Chevy Chase', 'MD'," +
		"'20852', 'Townhouse', 'Bad Shape', 3, 2.5, 3, 0, 3," +
		"1992, 415665.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
		"VALUES('207850', '14250 Parkdoll Rd', 'Rockville', 'MD'," +
		"'20854', 'Townhouse', 'Good', 3, 2.5, 2, 1, 2," +
		"1988, 325995.00);" +

		"INSERT INTO Properties(City, PropertyType, Bedrooms," +
		"YearBuilt, MarketValue)" +
		"VALUES('Washington', 'Townhouse', 4, 1975, 366775.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
		"YearBuilt, MarketValue)" +
"VALUES('288540', '10340 Helmes Street #408', 'Silver Spring', 'MD'," +
		"'20906', 'Condominium', 'Good', 1, 1, 2000, 242775.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('247472', '1008 Coppen Street', 'Silver Spring', 'MD'," +
		"'20906', 'Single Family', 'Excellent'," +
		"3, 3, 3, 1, 3, 1996, 625450.00);" +

		"INSERT INTO Properties(City, ZIPCode, PropertyType, " +
		"Stories, YearBuilt, MarketValue)" +
		"VALUES('Chevy Chase', '20956', 'Single Family', " +
		"3, 2001, 525450.00);" +

		"INSERT INTO Properties(Address, City, State," +
		"PropertyType, Condition, Bedrooms, MarketValue)" +
		"VALUES('686 Herod Ave #D04', 'Takoma Park', 'MD'," +
		"'Condominium', 'Excellent', 2, 360885.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
		"VALUES('297446', '14005 Sniders Blvd', 'Laurel', 'MD'," +
		"'20707', 'Townhouse', 'Needs Repair'," +
		"4, 1.5, 3, 1, 2, 2002, 412885.00);" +

	"INSERT INTO Properties(City, ZIPCode, Condition, Bedrooms," +
		"Stories, YearBuilt)" +
		"VALUES('Silver Spring', '20905', 'Good'," +
		"4, 2, 1965);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
		"VALUES('924792', '680 Prushia Rd', 'Washington', 'DC'," +
		"'20008', 'Single Family', 'Good'," +
		"5, 3.5, 3, 0, 3, 2000, 555885.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('294796', '14688 Parrison Street', 'College Park', 'MD'," +
		"'20742', 'Single Family', 'Excellent'," +
		"5, 2.5, 2, 1, 2, 1995, 485995.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
		"YearBuilt, MarketValue)" +
	"VALUES('811155', '10340 Helmes Street #1012', 'Silver Spring'," +
		"'MD', '20906', 'Condominium', 'Good'," +
		"1, 1, 2000, 252775.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('447597', '4201 Vilamar Ave', 'Hyattsville', 'MD'," +
		"'20782', 'Townhouse', 'Excellent'," +
		"3, 2, 2, 1, 3, 1992, 365880.00);" +

		"INSERT INTO Properties(Address, ZIPCode, Bathrooms)" +
		"VALUES('1622 Rombard Str', 20904, 2.5);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('297415', '980 Phorwick Street', 'Washington', 'DC'," +
		"'20004', 'Single Family', 'Good'," +
		"4, 3.5, 3, 3, 1, 2004, 735475.00);" +

	"INSERT INTO Properties(PropertyNumber, Address, City, State," +
		"ZIPCode, PropertyType, Condition, Bedrooms, Bathrooms," +
	"FinishedBasement, IndoorGarage, Stories, YearBuilt, MarketValue)" +
	"VALUES('475974', '9015 Marvin Crow Ave', 'Gaithersburg', 'MD'," +
		"'20872', 'Single Family', 'Needs Repair'," +
		"4, 2.5, 3, 1, 1, 1965, 615775.00);";


		SqlCommand cmdAltairRealtors1 =
			new SqlCommand(strAltairRealtors1,
		cnnAltairRealtors1);

		cnnAltairRealtors1.Open();
		cmdAltairRealtors1.ExecuteNonQuery();

MessageBox.Show("Some records have been created in the Properties table.");
	    }
	}
    }
}

Execute the application
Close the form and return to your programming environment
Delete the whole code in the Load event
Return to the form
From the Menu & Toolbars section of the Toolbox, click ContextMenuStrip and click the form
Name it cmnProperties

Create the menu items as follows:

Text	(Name)	Image
Filter by &Selection	mnuFilterBySelection	filtsel.ico
Filter &Excluding Selection	mnuFilterExclSel	filtexcl.ico
Separator
Sort &Ascending	mnuSortAscending	ascending.ico
Sort &Descending	mnuSortDescending	descending.ico
Separator
&Remove Filter/Sort	mnuRemoveFilterSort	rmvfiltsrt.ico

Design the form as follows:

Control	Text	Name	Other Properties
DataGridView		dgvProperties	Anchor: Top, Bottom, Left, Right ContextMenuStrip: cmnProperties
GroupBox	Fields to Show	grpFieldsToShow	Anchor: Bottom, Left, Right
RadioButton	Show all Fields	rdoShowAllFields
RadioButton	Show Only	rdoShowSomeFields
CheckedListBox		clbColumns	CheckOnClick: True MultiColumn: True Anchor: Bottom, Left, Right
Button	Execute	btnExecute	Anchor: Bottom, Right
Button	Close	btnClose	Anchor: Bottom, Right

Double-click an unoccupied area of the form and implement the Load event as follows:

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

namespace AltairRealtors6
{
    public partial class AltairRealtors : Form
    {
	public AltairRealtors()
    	{
	    InitializeComponent();
	}

	private void AltairRealtors_Load(object sender, EventArgs e)
	{
	    using (SqlConnection cnnProperties =
		new SqlConnection("Data Source=(local);" +
				  "Database='AltairRealtors1';" +
				  "Integrated Security='SSPI';"))
	    {
		string strSelect = "SELECT * FROM Properties;";

		SqlCommand cmdProperties = new SqlCommand(strSelect,
						cnnProperties);
		SqlDataAdapter sdaProperties =
			new SqlDataAdapter(cmdProperties);
		BindingSource bsProperties = new BindingSource();

		DataSet dsProperties = new DataSet("PropertiesSet");
		sdaProperties.Fill(dsProperties);

		cnnProperties.Open();
		bsProperties.DataSource = dsProperties.Tables[0];

		dgvProperties.DataSource = bsProperties;
		foreach (DataColumn col in dsProperties.Tables[0].Columns)
		    clbColumns.Items.Add(col.ColumnName);
	    }

	    rdoShowAllFields.Checked = true;
	}
    }
}

Return to the form and double-click the Execute button

Implement its Click event as follows:

private void btnExecute_Click(object sender, EventArgs e)
{
    using (SqlConnection cnnProperties =
	new SqlConnection("Data Source=(local);" +
			  "Database='AltairRealtors1';" +
			  "Integrated Security='SSPI';"))
   {
	string strColumns = "";

	foreach (string str in clbColumns.CheckedItems)
	    strColumns = strColumns + ", " + str;

	string strResult = "";

	if (rdoShowAllFields.Checked == true)
	    strResult = "SELECT * FROM Properties";
	else
	    strResult = "SELECT " +
			strColumns.Substring(1) +
			" FROM Properties";

	SqlCommand cmdProperties =
		new SqlCommand(strResult, cnnProperties);
	SqlDataAdapter sdaProperties =
		new SqlDataAdapter(cmdProperties);
	BindingSource bsProperties = new BindingSource();

	DataSet dsProperties = new DataSet("PropertiesSet");
	sdaProperties.Fill(dsProperties);

	cnnProperties.Open();
	bsProperties.DataSource = dsProperties.Tables[0];

	dgvProperties.DataSource = bsProperties;
    }
}

Return to the form and double-click the checked list box

Implement its event as follows:

private void clbColumns_SelectedIndexChanged(object sender, EventArgs e)
{
    if (clbColumns.CheckedItems.Count < 1)
	rdoShowAllFields.Checked = true;
    else
	rdoShowSomeFields.Checked = true;
}

Return to the form and double-click the Close button

Implement its event as follows:

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

Execute the application to see the result
Click a few check boxed in the bottom control
Click the Execute button
Close the form and return to your programming environment

Sorting the Records in SQL

In SQL, to specify the sorting order, use the ORDER BY expression. The formula to follow is:

SELECT What FROM WhatObject ORDER BY WhatField;

The column used as the basis must be recognized as part of the selected columns. For example, to get a list of students in alphabetical order based on the LastName column, you can use the following statement:

SELECT FirstName, 
       LastName, 
       DateOfBirth, 
       Sex
FROM Students
ORDER BY LastName;

This would produce:

Using the SQL

In the same way, you can get the list of girls followed by the list of boys by ordering the list in alphabetical order based on the Sex column. The statement to get this result can be written as follows:

SELECT FirstName, LastName, Gender, EmailAddress
FROM Students
ORDER BY Gender

As another example, to list all students arranged in alphabetical order by their last name, you can change the statement as follows:

SELECT * FROM Students
ORDER BY LastName

By default, records are ordered in ascending order. Nevertheless, the ascending order is controlled using the ASC keyword specified after the based field. For example, to sort the last names in ascending order including the first and last names, you would use a statement as follows:

SELECT * FROM Students
ORDER BY LastName ASC

On the other hand, if you want to sort records in reverse order, you can use the DESC keyword instead. It produces the opposite result to the ASC effect. Here is an example:

SELECT FirstName,
       LastName,
       Gender,
       ParentsNames,
       SPHome
FROM Students
ORDER BY LastName DESC;

This would produce:

Sorting Records

Practical Learning: Sorting the Records

Change the design of the form as follows:

Control	Text	Name	Other Properties
Label	Arrange
ComboBox		cbxColumns	DropDownStyle: DropDownList
Label	in
ComboBox		cbxAscendingDescending	DropDownStyle: DropDownList Items: Ascending Order Descending Order

Double-click an unoccupied area of the form and change the Load event as follows:

private void AltairRealtors_Load(object sender, EventArgs e)
{
    // Open a connection to the database
    using (SqlConnection cnnProperties =
	new SqlConnection("Data Source=(local);" +
			  "Database='AltairRealtors1';" +
			  "Integrated Security='SSPI';"))
    {
	// This statement creates a list of all properties
	string strSelect = "SELECT * FROM Properties;";
	// This data set will hold the tables of the database
	DataSet dsProperties = new DataSet("PropertiesSet");

	// Create a command to perform on the connection
	SqlCommand cmdProperties = new SqlCommand(strSelect,
						  cnnProperties);

	// Create a data adapter that will populate the data set
	SqlDataAdapter sdaProperties =
		new SqlDataAdapter(cmdProperties);

	// Create a binding source
	BindingSource bsProperties = new BindingSource();

	// Fill the data set with the values
	sdaProperties.Fill(dsProperties);

	// Open the connection
	cnnProperties.Open();

	// Get the table from the data set
	DataTable tblProperties = dsProperties.Tables[0];
	// Assign that table to the binding source
	bsProperties.DataSource = tblProperties;

	// Apply that binding source to the data grid view
	dgvProperties.DataSource = bsProperties;

	// Get a list of the columns of the table and
	// put them the names of those columns in the checked list box
	foreach (DataColumn col in dsProperties.Tables[0].Columns)
	{
	    clbColumns.Items.Add(col.ColumnName);
	    cbxColumns.Items.Add(col.ColumnName);
	}

	rdoShowAllFields.Checked = true;
	cbxColumns.SelectedIndex = 0;
	cbxAscendingDescending.SelectedIndex = 0;
    }
}

Change the code of the Click event of the Execute button as follows:

private void btnExecute_Click(object sender, EventArgs e)
{
    // Open a connection to the database
    using (SqlConnection cnnProperties =
	new SqlConnection("Data Source=(local);" +
			  "Database='AltairRealtors1';" +
			  "Integrated Security='SSPI';"))
    {
	// Get the list of columns checked in the list box
	// and put it in the Arrange combo box
	string strColumns = "";

	foreach (string str in clbColumns.CheckedItems)
	    strColumns = strColumns + ", " + str;

	// Find out what radio button is selected and use it
	// to know what column(s) will be used
	string strResult = "";

	if (rdoShowAllFields.Checked == true)
	    strResult = "SELECT * FROM Properties";
	else
	    strResult = "SELECT " +
			strColumns.Substring(1) +
			" FROM Properties";

	// Find out what sort order is selected and apply it
	if (cbxAscendingDescending.Text == "Ascending Order")
	  strResult = strResult + " ORDER BY " + cbxColumns.Text + " ASC;";
	else
	  strResult = strResult + " ORDER BY " + cbxColumns.Text + " DESC;";

	// Create a command to execute on the database
	SqlCommand cmdProperties =
	    new SqlCommand(strResult, cnnProperties);
	// Create a data adapter that will populate the data set
	SqlDataAdapter sdaProperties =
	    new SqlDataAdapter(cmdProperties);
	// Create a binding source
	BindingSource bsProperties = new BindingSource();
	// Create a data set
	DataSet dsProperties = new DataSet("PropertiesSet");

	// Fill the data set with the records in the data adapter
	sdaProperties.Fill(dsProperties);

	// Open the connection
	cnnProperties.Open();
	// Assign the Properties table to the binding source
	bsProperties.DataSource = dsProperties.Tables[0];

	// Assign the binding source to the data grid view
	dgvProperties.DataSource = bsProperties;
    }
}

Return to the form and double-click the combo box on the right side of the Arrange label

Implement the SelectedIndexChanged event as follows:

private void clbColumns_SelectedIndexChanged(object sender, EventArgs e)
{
    // This list will hold the names of checked columns in the list box
    List<string> lstColumns = new List<string>();

    // Assist the user with checking the radio buttons
    // based on the contents of the list box
    if (clbColumns.CheckedItems.Count < 1)
	rdoShowAllFields.Checked = true;
    else
	rdoShowSomeFields.Checked = true;

    // If the second radio button is selected, get the columns 
    // checked in the list box and add them to the Arrange combo box
    if (rdoShowSomeFields.Checked == true)
    {
	cbxColumns.Items.Clear();

	foreach (object objItem in clbColumns.CheckedItems)
	    cbxColumns.Items.Add(objItem);

	cbxColumns.SelectedIndex = 0;
    }
}

Execute application and test the form
Close the form and return to your programming environment

Sorting the Records in the Data Grid View

If you use a data grid view in your application, you can sort records without writing a single line of code. To sort the records based on a particular column, click the column header. After clicking for the first time, the column is sorted alphabetically, incrementally, or chronologically and an up-pointing arrow button would appear on the column header. Here is an example on the City column:

Sorting Records Using the Data Grid View

To sort records in reverse order based on a particular column, you can click the column again. Or, you must first click the column header to sort in order, then click the same column header again to reverse. When the records are sorted in reverse, a down-pointing arrow button would appear on the column header. Here is an example on the ZIPCode column:

Sorting Records Using the Data Grid View

Practical Learning: Sorting the Records Using the Data Grid View

Right-click the form and click View Code.
In the top section of the class, declare a DataGridViewColumn variable named colSelected:

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

namespace AltairRealtors6c
{
    public partial class AltairRealtors : Form
    {
	DataGridViewColumn colSelected;

  	public AltairRealtors()
	{
	    InitializeComponent();
	}

	. . . No Change

In the Load event, initialize the new variable using the default constructor of its class:

private void AltairRealtors_Load(object sender, EventArgs e)
{
    colSelected = new DataGridViewColumn();

    . . . No Change
}

Return to the form

In the Events section of the Properties window, double-click MouseDown and implement the event as follows:

private void dgvProperties_MouseDown(object sender, MouseEventArgs e)
{
    // Identity the point where the mouse landed
    DataGridView.HitTestInfo hti = dgvProperties.HitTest(e.X, e.Y);
    // Create a cell reference based on the coordinates of the mouse
    DataGridViewCell celSelected = 
	dgvProperties.Rows[hti.RowIndex].Cells[hti.ColumnIndex];
 
    // Just in case the user right-clicked, select that cell
    dgvProperties.CurrentCell = celSelected;

    // Identify the selected column and initialize our variable with it
    colSelected = dgvProperties.Columns[hti.ColumnIndex];
}

Return to the form and, under it, click the cmnProperties context menu

On the form, under ContextMenuStrip, double-click Sort Ascending, and implement the event as follows:

private void mnuSortAscending_Click(object sender, EventArgs e)
{
    // Since we know what column is going to be used to sort the record, 
    // synchronize it with the Arrange combo box
    cbxColumns.Text = colSelected.Name;
    // Since the user clicked Ascending, synchronize with the in combo box
    cbxAscendingDescending.SelectedIndex = 0;
    // Sort the records using the data grid view
    dgvProperties.Sort(colSelected, ListSortDirection.Ascending);
}

Return to the form and double-click Sort Descending

Implement the event as follows:

private void mnuSortDescending_Click(object sender, EventArgs e)
{
    // Since we know what column is going to be used to sort the record, 
    // synchronize it with the Arrange combo box
    cbxColumns.Text = colSelected.Name;
    // Since the user clicked Ascending, synchronize with the in combo box
    cbxAscendingDescending.SelectedIndex = 1;
    // Sort the records using the data grid view
    dgvProperties.Sort(colSelected, ListSortDirection.Descending);
}

Execute the application
Right-click a value in a column and sort the records
Close the form and return to your programming environment

Published on Friday 04 January 2008


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