DataList.SelectedItem Property

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

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.

Gets the selected item in the DataList control.

public:
 virtual property System::Web::UI::WebControls::DataListItem ^ SelectedItem { System::Web::UI::WebControls::DataListItem ^ get(); };

[System.ComponentModel.Browsable(false)]
public virtual System.Web.UI.WebControls.DataListItem SelectedItem { get; }

[<System.ComponentModel.Browsable(false)>]
member this.SelectedItem : System.Web.UI.WebControls.DataListItem

Public Overridable ReadOnly Property SelectedItem As DataListItem

Property Value

DataListItem

A DataListItem that represents the item selected in the DataList control.

Attributes: BrowsableAttribute

Examples

The following code example demonstrates how to use the SelectedItem property to display the contents of the selected item in the DataList 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" >
<head>
    <title>DataList SelectedItem Example</title>
<script language="C#" runat="server">

      public DataTable Cart;
      public DataView CartView;

      void Page_Load(Object sender, EventArgs e) 
      {
         if (Session["DL3_ShoppingCart"] == null) 
         {
            Cart = new DataTable();
            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["DL3_ShoppingCart"] = Cart;

            // First Load - Create some data.
            for (int i=1; i<=9; i++) 
            {
               DataRow dr = Cart.NewRow();
               dr[0] = ((i%2)+1).ToString();
               dr[1] = "Item " + i.ToString();
               dr[2] = (1.23 * (i+1)).ToString();
               Cart.Rows.Add(dr);
            }
         }
         else
            Cart = (DataTable)Session["DL3_ShoppingCart"];

         CartView = new DataView(Cart);
         CartView.Sort = "Item";
         if (!IsPostBack)
            BindList();
      }

      void BindList() 
      {
         DataList1.DataSource= CartView;
         DataList1.DataBind();
      }

      void DataList_ItemCommand(Object sender, DataListCommandEventArgs e) 
      {
         DataList1.SelectedIndex = e.Item.ItemIndex;
         BindList();
         Label4.Text = "You selected: "  + 
                       ((Label)DataList1.SelectedItem.FindControl("Label1")).Text;
      }

      void Button_Click(Object sender, EventArgs e)
      { 
         if (DataList1.SelectedItem != null)
         {
            DataList1.SelectedItem.ForeColor = System.Drawing.Color.Red;
         }
      }

   </script>

</head>
<body>

   <form id="form1" runat="server">

      <h3>DataList SelectedItem Example</h3>
      <p></p>
       
      <asp:DataList id="DataList1" runat="server"
           GridLines="Both"
           CellPadding="3"
           CellSpacing="0"           
           OnItemCommand="DataList_ItemCommand">

         <HeaderStyle BackColor="#aaaadd">
         </HeaderStyle>

         <AlternatingItemStyle BackColor="Gainsboro">
         </AlternatingItemStyle>

         <SelectedItemStyle BackColor="lightgreen">
         </SelectedItemStyle>

         <HeaderTemplate>

            Items

         </HeaderTemplate>
         
         <ItemTemplate>

            <asp:LinkButton id="button1" 
                 Text="Select" 
                 CommandName="select"
                 runat="server"/>
            <%# ((DataRowView)Container.DataItem)["Item"]  %>

         </ItemTemplate>
              
         <SelectedItemTemplate>

            Item:
            <asp:Label id="Label1" 
                 Text='<%# ((DataRowView)Container.DataItem)["Item"] %>' 
                 runat="server"/>

            <br />

            Quantity:
            <asp:Label id="Label2" 
                 Text='<%# ((DataRowView)Container.DataItem)["Qty"] %>' 
                 runat="server"/>

            <br />

            Price:
            <asp:Label id="Label3" 
                 Text='<%# DataBinder.Eval(Container.DataItem, "Price") %>' 
                 runat="server"/>

         </SelectedItemTemplate>

      </asp:DataList>

      <br /><br />

      <asp:Label id="Label4"
           runat="server"/>

      <br /><br />

      <asp:Button id="Button2"
           Text="Change Text to Red" 
           OnClick="Button_Click"
           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" >
<head>
    <title>DataList SelectedItem Example</title>
<script language="VB" runat="server">
 
    Dim Cart As DataTable
    Dim CartView As DataView

    Sub Page_Load(sender As Object, e As EventArgs)
        If Session("DL3_ShoppingCart") Is Nothing Then
            Cart = New DataTable()
            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("DL3_ShoppingCart") = Cart
            
            ' First Load - Create some data.
            Dim i As Integer
            For i = 1 To 9
                Dim dr As DataRow = Cart.NewRow()
                dr(0) =(i Mod 2 + 1).ToString()
                dr(1) = "Item " & i.ToString()
                dr(2) =(1.23 *(i + 1)).ToString()
                Cart.Rows.Add(dr)
            Next i
        Else
            Cart = CType(Session("DL3_ShoppingCart"), DataTable)
        End If 
        CartView = New DataView(Cart)
        CartView.Sort = "Item"
        If Not IsPostBack Then
            BindList()
        End If
    End Sub 'Page_Load
     
    Sub BindList()
        DataList1.DataSource = CartView
        DataList1.DataBind()
    End Sub 'BindList

    Sub DataList_ItemCommand(sender As Object, e As DataListCommandEventArgs)
        DataList1.SelectedIndex = e.Item.ItemIndex
        BindList()
        Label4.Text = "You selected: " & CType(DataList1.SelectedItem.FindControl("Label1"), Label).Text
    End Sub 'DataList_ItemCommand

    Sub Button_Click(sender As Object, e As EventArgs)
        If Not (DataList1.SelectedItem Is Nothing) Then
            DataList1.SelectedItem.ForeColor = System.Drawing.Color.Red
        End If
    End Sub 'Button_Click

</script>

</head>
<body>

   <form id="form1" runat="server">

      <h3>DataList SelectedItem Example</h3>
      <p></p>
       
      <asp:DataList id="DataList1" runat="server"
           GridLines="Both"
           CellPadding="3"
           CellSpacing="0"           
           OnItemCommand="DataList_ItemCommand">

         <HeaderStyle BackColor="#aaaadd">
         </HeaderStyle>

         <AlternatingItemStyle BackColor="Gainsboro">
         </AlternatingItemStyle>

         <SelectedItemStyle BackColor="lightgreen">
         </SelectedItemStyle>

         <HeaderTemplate>

            Items

         </HeaderTemplate>
         
         <ItemTemplate>

            <asp:LinkButton id="button1" 
                 Text="Select" 
                 CommandName="select"
                 runat="server"/>
            <%# (CType(Container.DataItem, DataRowView))("Item")%>

         </ItemTemplate>
              
         <SelectedItemTemplate>

            Item:
            <asp:Label id="Label1" 
                 Text='<%# (CType(Container.DataItem, DataRowView))("Item")%>' 
                 runat="server"/>

            <br />

            Quantity:
            <asp:Label id="Label2" 
                 Text='<%# (CType(Container.DataItem, DataRowView))("Qty")%>' 
                 runat="server"/>

            <br />

            Price:
            <asp:Label id="Label3" 
                 Text='<%# DataBinder.Eval(Container.DataItem, "Price")%>' 
                 runat="server"/>

         </SelectedItemTemplate>

      </asp:DataList>

      <br /><br />

      <asp:Label id="Label4"
           runat="server"/>

      <br /><br />

      <asp:Button id="Button2"
           Text="Change Text to Red" 
           OnClick="Button_Click"
           runat="server"/>

   </form>

</body>
</html>

Remarks

Use the SelectedItem property to get a DataListItem object that represents the selected item in the DataList control. This object can then be used to access the properties of the selected item.

Applies to

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