DataGrid.SelectedIndex Property
Definition
Important
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Gets or sets the index of the selected item in the DataGrid control.
public:
virtual property int SelectedIndex { int get(); void set(int value); };[System.ComponentModel.Bindable(true)]
public virtual int SelectedIndex { get; set; }[<System.ComponentModel.Bindable(true)>]
member this.SelectedIndex : int with get, setPublic Overridable Property SelectedIndex As IntegerProperty Value
The index of the selected item in the DataGrid control.
- Attributes
Exceptions
The specified index is less than -1.
Examples
The following code example demonstrates how to use the SelectedIndex property to determine the index number of the selected item in the DataGrid control. It also shows how to select and deselect an item programmatically.
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script language="C#" runat="server">
DataTable Cart = new DataTable();
DataView CartView;
void Page_Load(Object sender, EventArgs e)
{
DataRow dr;
if (Session["ShoppingCart"] == null)
{
Cart.Columns.Add(new DataColumn("Qty", typeof(String)));
Cart.Columns.Add(new DataColumn("Item", typeof(String)));
Cart.Columns.Add(new DataColumn("Price", typeof(String)));
Session["ShoppingCart"] = Cart;
// Create rows and add sample data.
for (int i = 1; i <= 9; i++)
{
dr = Cart.NewRow();
if (i % 2 != 0)
dr[0] = "2";
else
dr[0] = "1";
dr[1] = "Item " + i.ToString();
dr[2] = (1.23 * (i + 1)).ToString();
Cart.Rows.Add(dr);
}
}
else
Cart = (DataTable)Session["ShoppingCart"];
CartView = new DataView(Cart);
CartView.Sort="Item";
if (!IsPostBack)
BindGrid();
}
void MyDataGrid_Select(Object sender, EventArgs e)
{
Label1.Text = "You selected " +
MyDataGrid.SelectedItem.Cells[1].Text +
".<br />" +
MyDataGrid.SelectedItem.Cells[1].Text +
" has an index number of " +
MyDataGrid.SelectedIndex.ToString() + ".";
}
void Select_Button_Click(Object sender, EventArgs e)
{
MyDataGrid.SelectedIndex = 4;
}
void UnSelect_Button_Click(Object sender, EventArgs e)
{
MyDataGrid.SelectedIndex = -1;
Label1.Text = "";
}
void BindGrid()
{
MyDataGrid.DataSource = CartView;
MyDataGrid.DataBind();
}
</script>
<head runat="server">
<title>DataGrid Selection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid Selection Example</h3>
<asp:DataGrid id="MyDataGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt"
OnSelectedIndexChanged="MyDataGrid_Select"
AutoGenerateColumns="false">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<SelectedItemStyle BackColor="Yellow">
</SelectedItemStyle>
<Columns>
<asp:ButtonColumn
HeaderText="Select Item"
ButtonType="LinkButton"
Text="Select"
CommandName="Select">
</asp:ButtonColumn>
<asp:BoundColumn
HeaderText="Item"
ReadOnly="true"
DataField="Item"/>
<asp:BoundColumn
HeaderText="Quantity"
DataField="Qty"/>
<asp:BoundColumn
HeaderText="Price"
DataField="Price"/>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="Button1"
Text="Select Item 5"
OnClick="Select_Button_Click"
runat="server"/>
<asp:Button id="Button2"
Text="Unselect Item"
OnClick="UnSelect_Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Label1" runat="server"/>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script language="VB" runat="server">
Dim Cart As New DataTable
Dim CartView As DataView
Sub Page_Load(sender As Object, e As EventArgs)
Dim dr As DataRow
If Session("ShoppingCart") Is Nothing Then
Cart.Columns.Add(New DataColumn("Qty", GetType(String)))
Cart.Columns.Add(New DataColumn("Item", GetType(String)))
Cart.Columns.Add(New DataColumn("Price", GetType(String)))
Session("ShoppingCart") = Cart
' Create rows and add sample data.
Dim i As Integer
For i = 1 To 9
dr = Cart.NewRow()
If i Mod 2 <> 0 Then
dr(0) = "2"
Else
dr(0) = "1"
End If
dr(1) = "Item " & i.ToString()
dr(2) =(1.23 *(i + 1)).ToString()
Cart.Rows.Add(dr)
Next i
Else
Cart = CType(Session("ShoppingCart"), DataTable)
End If
CartView = New DataView(Cart)
CartView.Sort = "Item"
If Not IsPostBack Then
BindGrid()
End If
End Sub 'Page_Load
Sub MyDataGrid_Select(sender As Object, e As EventArgs)
Label1.Text = "You selected " & MyDataGrid.SelectedItem.Cells(1).Text & _
".<br />" & MyDataGrid.SelectedItem.Cells(1).Text & " has an index number of " & _
MyDataGrid.SelectedIndex.ToString() & "."
End Sub 'MyDataGrid_Select
Sub Select_Button_Click(sender As Object, e As EventArgs)
MyDataGrid.SelectedIndex = 4
End Sub 'Select_Button_Click
Sub UnSelect_Button_Click(sender As Object, e As EventArgs)
MyDataGrid.SelectedIndex = - 1
Label1.Text = ""
End Sub 'UnSelect_Button_Click
Sub BindGrid()
MyDataGrid.DataSource = CartView
MyDataGrid.DataBind()
End Sub 'BindGrid
</script>
<head runat="server">
<title>DataGrid Selection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid Selection Example</h3>
<asp:DataGrid id="MyDataGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt"
OnSelectedIndexChanged="MyDataGrid_Select"
AutoGenerateColumns="false">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<SelectedItemStyle BackColor="Yellow">
</SelectedItemStyle>
<Columns>
<asp:ButtonColumn
HeaderText="Select Item"
ButtonType="LinkButton"
Text="Select"
CommandName="Select">
</asp:ButtonColumn>
<asp:BoundColumn
HeaderText="Item"
ReadOnly="true"
DataField="Item"/>
<asp:BoundColumn
HeaderText="Quantity"
DataField="Qty"/>
<asp:BoundColumn
HeaderText="Price"
DataField="Price"/>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="Button1"
Text="Select Item 5"
OnClick="Select_Button_Click"
runat="server"/>
<asp:Button id="Button2"
Text="Unselect Item"
OnClick="UnSelect_Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Label1" runat="server"/>
</form>
</body>
</html>
Remarks
Use the SelectedIndex property to determine the index of the item selected by the user in the DataGrid control. You can also use this property to programmatically specify which item is selected in the DataGrid control.
To deselect an item in the DataGrid control, set this property to -1.
Applies to
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