DataList.SelectedIndex Property
Gets or sets the index of the selected item in the DataList control.
[Visual Basic] Public Overridable Property SelectedIndex As Integer [C#] public virtual int SelectedIndex {get; set;} [C++] public: __property virtual int get_SelectedIndex(); public: __property virtual void set_SelectedIndex(int); [JScript] public function get SelectedIndex() : int; public function set SelectedIndex(int);
Property Value
The index of the selected item in the DataList control.
Remarks
Use the SelectedIndex property to programmatically specify the selected item in the DataList control. You can also use this property to determine the index of the selected item.
Note The SelectedIndex property is zero based.
To deselect an item, set the SelectedIndex property to -1.
Example
[Visual Basic, C#] The following example demonstrates how to use the SelectedIndex property to specify the selected item in the DataList control.
[Visual Basic, C#] Note The following code sample uses the single-file code model and may not work correctly if copied directly into a code-behind file. This code sample must be copied into an empty text file that has an .aspx extension. For more information on the Web Forms code model, see Web Forms Code Model.
[Visual Basic] <%@ Page Language="VB" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <head> <script runat="server"> Function CreateDataSource() As ICollection ' Create sample data for the DataList control. Dim dt As DataTable = New DataTable() Dim dr As DataRow ' Define the columns of the table. dt.Columns.Add(New DataColumn("Item", GetType(Int32))) dt.Columns.Add(New DataColumn("Qty", GetType(Int32))) dt.Columns.Add(New DataColumn("Price", GetType(Double))) ' Populate the table with sample values. Dim i As Integer For i = 0 To 8 dr = dt.NewRow() dr(0) = i dr(1) = i * 2 dr(2) = 1.23 * (i + 1) dt.Rows.Add(dr) Next i Dim dv As DataView = New DataView(dt) Return dv End Function Sub Page_Load(sender As Object, e As EventArgs) ' Load sample data only once, when the page is first loaded. If Not IsPostBack Then ItemsList.DataSource = CreateDataSource() ItemsList.DataBind() End If End Sub Sub Item_Command(sender As Object, e As DataListCommandEventArgs) ' Set the SelectedIndex property to select an item in the DataList. ItemsList.SelectedIndex = e.Item.ItemIndex ' Rebind the data source to the DataList to refresh the control. ItemsList.DataSource = CreateDataSource() ItemsList.DataBind() End Sub </script> </head> <body> <form runat="server"> <h3>DataList Select Example</h3> Click <b>Select</b> to select an item. <br><br> <asp:DataList id="ItemsList" GridLines="Both" CellPadding="3" CellSpacing="0" OnItemCommand="Item_Command" runat="server"> <HeaderStyle BackColor="#aaaadd"> </HeaderStyle> <AlternatingItemStyle BackColor="Gainsboro"> </AlternatingItemStyle> <SelectedItemStyle BackColor="Yellow"> </SelectedItemStyle> <HeaderTemplate> Items </HeaderTemplate> <ItemTemplate> <asp:LinkButton id="SelectButton" Text="Select" CommandName="Select" runat="server"/> Item <%# DataBinder.Eval(Container.DataItem, "Item") %> </ItemTemplate> <SelectedItemTemplate> Item: <asp:Label id="ItemLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Item") %>' runat="server"/> <br> Quantity: <asp:Label id="QtyLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Qty") %>' runat="server"/> <br> Price: <asp:Label id="PriceLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>' runat="server"/> </SelectedItemTemplate> </asp:DataList> </form> </body> </html> [C#] <%@ Page Language="C#" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <head> <script runat="server"> ICollection CreateDataSource() { // Create sample data for the DataList control. DataTable dt = new DataTable(); DataRow dr; // Define the columns of the table. dt.Columns.Add(new DataColumn("Item", typeof(Int32))); dt.Columns.Add(new DataColumn("Qty", typeof(Int32))); dt.Columns.Add(new DataColumn("Price", typeof(double))); // Populate the table with sample values. for (int i = 0; i < 9; i++) { dr = dt.NewRow(); dr[0] = i; dr[1] = i * 2; dr[2] = 1.23 * (i + 1); dt.Rows.Add(dr); } DataView dv = new DataView(dt); return dv; } void Page_Load(Object sender, EventArgs e) { // Load sample data only once, when the page is first loaded. if (!IsPostBack) { ItemsList.DataSource = CreateDataSource(); ItemsList.DataBind(); } } void Item_Command(Object sender, DataListCommandEventArgs e) { // Set the SelectedIndex property to select an item in the DataList. ItemsList.SelectedIndex = e.Item.ItemIndex; // Rebind the data source to the DataList to refresh the control. ItemsList.DataSource = CreateDataSource(); ItemsList.DataBind(); } </script> </head> <body> <form runat="server"> <h3>DataList Select Example</h3> Click <b>Select</b> to select an item. <br><br> <asp:DataList id="ItemsList" GridLines="Both" CellPadding="3" CellSpacing="0" OnItemCommand="Item_Command" runat="server"> <HeaderStyle BackColor="#aaaadd"> </HeaderStyle> <AlternatingItemStyle BackColor="Gainsboro"> </AlternatingItemStyle> <SelectedItemStyle BackColor="Yellow"> </SelectedItemStyle> <HeaderTemplate> Items </HeaderTemplate> <ItemTemplate> <asp:LinkButton id="SelectButton" Text="Select" CommandName="Select" runat="server"/> Item <%# DataBinder.Eval(Container.DataItem, "Item") %> </ItemTemplate> <SelectedItemTemplate> Item: <asp:Label id="ItemLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Item") %>' runat="server"/> <br> Quantity: <asp:Label id="QtyLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Qty") %>' runat="server"/> <br> Price: <asp:Label id="PriceLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>' runat="server"/> </SelectedItemTemplate> </asp:DataList> </form> </body> </html>
[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Platforms: Windows 2000, Windows XP Professional, Windows Server 2003 family
See Also
DataList Class | DataList Members | System.Web.UI.WebControls Namespace | SelectedItem | SelectedItemStyle | SelectedItemTemplate