DataListItem.ItemIndex Property
Definition
Important
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Gets the index of the DataListItem object from the Items collection of the control.
public:
virtual property int ItemIndex { int get(); };public virtual int ItemIndex { get; }member this.ItemIndex : intPublic Overridable ReadOnly Property ItemIndex As IntegerProperty Value
The index of the DataListItem object from the Items collection.
Examples
The following example demonstrates how to use the ItemIndex property to display the index number of the DataListItem object from the Items collection of the control.
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 ASP.NET Web Forms Page Code Model.
<%@ 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">
ICollection CreateDataSource()
{
DataTable dt = new DataTable();
DataRow dr;
dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
for (int i = 0; i < 10; i++)
{
dr = dt.NewRow();
dr[0] = "Item " + i.ToString();
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
if (!IsPostBack)
{
DataList1.DataSource = CreateDataSource();
DataList1.DataBind();
}
}
void Button_Click(Object sender, EventArgs e)
{
Label1.Text = "The ItemIndex of each item in the DataList are: <br />";
foreach (DataListItem item in DataList1.Items)
{
Label1.Text += "<br />" + item.ItemIndex.ToString() + " - " +
((DataBoundLiteralControl)item.Controls[1]).Text;
}
}
</script>
<head runat="server">
<title>DataListItem ItemIndex Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataListItem ItemIndex Example</h3>
<asp:DataList id="DataList1" runat="server"
BorderColor="black"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<HeaderTemplate>
Items
</HeaderTemplate>
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "StringValue") %>
</ItemTemplate>
</asp:DataList>
<br /><br />
<asp:Button id="Button1"
Text="Display ItemIndex for Items in the DataList"
OnClick="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">
Function CreateDataSource() As ICollection
Dim dt As New DataTable()
Dim dr As DataRow
dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
Dim i As Integer
For i = 0 To 9
dr = dt.NewRow()
dr(0) = "Item " & i.ToString()
dt.Rows.Add(dr)
Next i
Dim dv As New DataView(dt)
Return dv
End Function 'CreateDataSource
Sub Page_Load(sender As Object, e As EventArgs)
If Not IsPostBack Then
DataList1.DataSource = CreateDataSource()
DataList1.DataBind()
End If
End Sub 'Page_Load
Sub Button_Click(sender As Object, e As EventArgs)
Label1.Text = "The ItemIndex of each item in the DataList are: <br />"
Dim item As DataListItem
For Each item In DataList1.Items
Label1.Text &= "<br />" & item.ItemIndex.ToString() & " - " & CType(item.Controls(1), DataBoundLiteralControl).Text
Next item
End Sub 'Button_Click
</script>
<head runat="server">
<title>DataListItem ItemIndex Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataListItem ItemIndex Example</h3>
<asp:DataList id="DataList1" runat="server"
BorderColor="black"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<HeaderTemplate>
Items
</HeaderTemplate>
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "StringValue") %>
</ItemTemplate>
</asp:DataList>
<br /><br />
<asp:Button id="Button1"
Text="Display ItemIndex for Items in the DataList"
OnClick="Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Label1"
runat="server"/>
</form>
</body>
</html>
Remarks
Use the ItemIndex property to determine the index number of the DataListItem object from the Items collection.
Note
This property only applies to data items in the DataList control. The ItemType property of the DataListItem object must be set to ListItemType.Item, ListItemType.AlternatingItem, ListItemType.SelectedItem, or ListItemType.EditItem.
