แก้ไข

แชร์ผ่าน


DataListItem.DataItem Property

Definition

Gets or sets a data item associated with the DataListItem object in the DataList control.

public:
 virtual property System::Object ^ DataItem { System::Object ^ get(); void set(System::Object ^ value); };
public virtual object DataItem { get; set; }
member this.DataItem : obj with get, set
Public Overridable Property DataItem As Object

Property Value

An Object that represents a data item in the DataList control.

Examples

The following example demonstrates how to use the DataItem property to display the contents of the data items 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" >
   <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("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(String)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
 
         // Populate the table with sample values.
         for (int i = 0; i < 9; i++) 
         {
            dr = dt.NewRow();
 
            dr[0] = i;
            dr[1] = "Description for item " + i.ToString();
            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_Created(Object sender, DataListItemEventArgs e)
      {

         if (e.Item.ItemType == ListItemType.Item || 
             e.Item.ItemType == ListItemType.AlternatingItem)
         {

            // Retrieve the Label control in the current DataListItem.
            Label PriceLabel = (Label)e.Item.FindControl("PriceLabel");

            // Retrieve the text of the CurrencyColumn from the DataListItem
            // and convert the value to a Double.
            Double Price = Convert.ToDouble(
                ((DataRowView)e.Item.DataItem).Row.ItemArray[2].ToString());

            // Format the value as currency and redisplay it in the DataList.
            PriceLabel.Text = Price.ToString("c");

         }

      }
 
   </script>
 
<head runat="server">
    <title>DataList ItemCreated Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemCreated Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           OnItemCreated="Item_Created"
           runat="server">

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

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

         <HeaderTemplate>

            List of items

         </HeaderTemplate>
               
         <ItemTemplate>

            Description: <br />
            <%# DataBinder.Eval(Container.DataItem, "StringValue") %>

            <br />

            Price: 
            <asp:Label id="PriceLabel"
                 runat="server"/>

         </ItemTemplate>
 
      </asp:DataList>
 
   </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 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("IntegerValue", GetType(Int32)))
         dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
         dt.Columns.Add(New DataColumn("CurrencyValue", 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) = "Description for item " & i.ToString()
            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_Created(sender As Object, e As DataListItemEventArgs)

         If e.Item.ItemType = ListItemType.Item Or _
             e.Item.ItemType = ListItemType.AlternatingItem Then


            ' Retrieve the Label control in the current DataListItem.
            Dim PriceLabel As Label = _
                CType(e.Item.FindControl("PriceLabel"), Label)

            ' Retrieve the text of the CurrencyColumn from the DataListItem
            ' and convert the value to a Double.
            Dim Price As Double = Convert.ToDouble( _
                (CType(e.Item.DataItem, DataRowView)).Row.ItemArray(2).ToString())

            ' Format the value as currency and redisplay it in the DataList.
            PriceLabel.Text = Price.ToString("c")

         End If

      End Sub
 
   </script>
 
<head runat="server">
    <title>DataList ItemCreated Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemCreated Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           OnItemCreated="Item_Created"
           runat="server">

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

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

         <HeaderTemplate>

            List of items

         </HeaderTemplate>
               
         <ItemTemplate>

            Description: <br />
            <%# DataBinder.Eval(Container.DataItem, "StringValue") %>

            <br />

            Price: 
            <asp:Label id="PriceLabel"
                 runat="server"/>

         </ItemTemplate>
 
      </asp:DataList>
 
   </form>
 
</body>
</html>

Remarks

Use the DataItem property to specify or determine the properties of a data item associated with the DataListItem object in the DataList control.

Note

This property only applies to data items in the DataList control. The ItemType property of the DataListItem object must be set to one of the ListItemType enumeration values.

Applies to

See also