GridView.SelectedIndexChanged Event
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Occurs when a row's Select button is clicked, but after the GridView control handles the select operation.
public:
event EventHandler ^ SelectedIndexChanged;public event EventHandler SelectedIndexChanged;member this.SelectedIndexChanged : EventHandler Public Custom Event SelectedIndexChanged As EventHandler Event Type
Examples
The following example demonstrates how to use the SelectedIndexChanged event to display the name of the customer in the selected row of the GridView control.
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void CustomersGridView_SelectedIndexChanged(Object sender, EventArgs e)
{
// Get the currently selected row using the SelectedRow property.
GridViewRow row = CustomersGridView.SelectedRow;
// Display the first name from the selected row.
// In this example, the third column (index 2) contains
// the first name.
MessageLabel.Text = "You selected " + row.Cells[2].Text + ".";
}
void CustomersGridView_SelectedIndexChanging(Object sender, GridViewSelectEventArgs e)
{
// Get the currently selected row. Because the SelectedIndexChanging event
// occurs before the select operation in the GridView control, the
// SelectedRow property cannot be used. Instead, use the Rows collection
// and the NewSelectedIndex property of the e argument passed to this
// event handler.
GridViewRow row = CustomersGridView.Rows[e.NewSelectedIndex];
// You can cancel the select operation by using the Cancel
// property. For this example, if the user selects a customer with
// the ID "ANATR", the select operation is canceled and an error message
// is displayed.
if (row.Cells[1].Text == "ANATR")
{
e.Cancel = true;
MessageLabel.Text = "You cannot select " + row.Cells[2].Text + ".";
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView Select Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView Select Example</h3>
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSource"
autogeneratecolumns="False"
autogenerateselectbutton="True"
selectedindex="1"
onselectedindexchanged="CustomersGridView_SelectedIndexChanged"
onselectedindexchanging="CustomersGridView_SelectedIndexChanging"
runat="server" DataKeyNames="CustomerID">
<Columns>
<asp:BoundField DataField="CustomerID"
HeaderText="CustomerID"
InsertVisible="False" ReadOnly="True"
SortExpression="CustomerID" />
<asp:BoundField DataField="FirstName"
HeaderText="FirstName"
SortExpression="FirstName" />
<asp:BoundField DataField="MiddleName"
HeaderText="MiddleName"
SortExpression="MiddleName" />
<asp:BoundField DataField="LastName"
HeaderText="LastName"
SortExpression="LastName" />
<asp:BoundField DataField="Phone"
HeaderText="Phone"
SortExpression="Phone" />
</Columns>
<selectedrowstyle backcolor="LightCyan"
forecolor="DarkBlue"
font-bold="true"/>
</asp:gridview>
<br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSource"
selectcommand="SELECT CustomerID, FirstName, MiddleName, LastName, Phone FROM SalesLT.Customer"
connectionstring="<%$ ConnectionStrings:AdventureWorksLTConnectionString %>"
runat="server"/>
</form>
</body>
</html>
<%@ Page language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub CustomersGridView_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
' Get the currently selected row using the SelectedRow property.
Dim row As GridViewRow = CustomersGridView.SelectedRow
' Display the first name from the selected row.
' In this example, the third column (index 2) contains
' the first name.
MessageLabel.Text = "You selected " & row.Cells(2).Text & "."
End Sub
Sub CustomersGridView_SelectedIndexChanging(ByVal sender As Object, ByVal e As GridViewSelectEventArgs)
' Get the currently selected row. Because the SelectedIndexChanging event
' occurs before the select operation in the GridView control, the
' SelectedRow property cannot be used. Instead, use the Rows collection
' and the NewSelectedIndex property of the e argument passed to this
' event handler.
Dim row As GridViewRow = CustomersGridView.Rows(e.NewSelectedIndex)
' You can cancel the select operation by using the Cancel
' property. For this example, if the user selects a customer with
' the ID "ANATR", the select operation is canceled and an error message
' is displayed.
If row.Cells(1).Text = "ANATR" Then
e.Cancel = True
MessageLabel.Text = "You cannot select " + row.Cells(2).Text & "."
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView Select Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView Select Example</h3>
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSource"
autogeneratecolumns="False"
autogenerateselectbutton="True"
selectedindex="1"
onselectedindexchanged="CustomersGridView_SelectedIndexChanged"
onselectedindexchanging="CustomersGridView_SelectedIndexChanging"
runat="server" DataKeyNames="CustomerID">
<Columns>
<asp:BoundField DataField="CustomerID"
HeaderText="CustomerID"
InsertVisible="False" ReadOnly="True"
SortExpression="CustomerID" />
<asp:BoundField DataField="FirstName"
HeaderText="FirstName"
SortExpression="FirstName" />
<asp:BoundField DataField="MiddleName"
HeaderText="MiddleName"
SortExpression="MiddleName" />
<asp:BoundField DataField="LastName"
HeaderText="LastName"
SortExpression="LastName" />
<asp:BoundField DataField="Phone"
HeaderText="Phone"
SortExpression="Phone" />
</Columns>
<selectedrowstyle backcolor="LightCyan"
forecolor="DarkBlue"
font-bold="true"/>
</asp:gridview>
<br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSource"
selectcommand="SELECT CustomerID, FirstName, MiddleName, LastName, Phone FROM SalesLT.Customer"
connectionstring="<%$ ConnectionStrings:AdventureWorksLTConnectionString %>"
runat="server"/>
</form>
</body>
</html>
Remarks
The SelectedIndexChanged event is raised when a row's Select button is clicked, but after the GridView control handles the select operation. This enables you to provide an event-handling method that performs a custom routine, such as updating a status label with the currently selected row, whenever this event occurs.
For more information about how to handle events, see Handling and Raising Events.
Applies to
See also
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