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DataList.SelectedItem Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets the selected item in the DataList control.

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

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.

Poznámka

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.

ASP.NET (C#) 
<%@ 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>

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

Produkt Verzie
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

See also