DataList Class (System.Web.UI.WebControls)

Switch View :
Classic
Lightweight
ScriptFree
DataList Class
A data bound list control that displays items using templates.

Namespace: System.Web.UI.WebControls
Assembly: System.Web (in system.web.dll)

Syntax
Visual Basic (Declaration)
<ControlValuePropertyAttribute("SelectedValue")> _
Public Class DataList
	Inherits BaseDataList
	Implements INamingContainer, IRepeatInfoUser
Visual Basic (Usage)
Dim instance As DataList
C#
[ControlValuePropertyAttribute("SelectedValue")] 
public class DataList : BaseDataList, INamingContainer, IRepeatInfoUser
C++
[ControlValuePropertyAttribute(L"SelectedValue")] 
public ref class DataList : public BaseDataList, INamingContainer, IRepeatInfoUser
J#
/** @attribute ControlValuePropertyAttribute("SelectedValue") */ 
public class DataList extends BaseDataList implements INamingContainer, IRepeatInfoUser
JScript
ControlValuePropertyAttribute("SelectedValue") 
public class DataList extends BaseDataList implements INamingContainer, IRepeatInfoUser
XAML
Not applicable.
Remarks

Use the DataList control to display a template-defined data bound list. The DataList control supports selecting and editing.

The contents of the DataList control can be manipulated by using templates. The following table lists the supported templates.

Template Name

Description

AlternatingItemTemplate

If defined, provides the content and layout for alternating items in the DataList. If not defined, ItemTemplate is used.

EditItemTemplate

If defined, provides the content and layout for the item currently being edited in the DataList. If not defined, ItemTemplate is used.

FooterTemplate

If defined, provides the content and layout for the footer section of the DataList. If not defined, a footer section will not be displayed.

HeaderTemplate

If defined, provides the content and layout for the header section of the DataList. If not defined, a header section will not be displayed.

ItemTemplate

Required template that provides the content and layout for items in the DataList.

SelectedItemTemplate

If defined, provides the content and layout for the currently selected item in the DataList. If not defined, ItemTemplate is used.

SeparatorTemplate

If defined, provides the content and layout for the separator between items in the DataList. If not defined, a separator will not be displayed.

At the very minimum, the ItemTemplate needs to be defined to display the items in the DataList control. Additional templates can be used to provide a custom look to the DataList control.

The appearance of the DataList control may be customized by setting the style properties for the different parts of the control. The following table lists the different style properties.

Style Property

Description

AlternatingItemStyle

Specifies the style for alternating items in the DataList control.

EditItemStyle

Specifies the style for the item being edited in the DataList control.

FooterStyle

Specifies the style for the footer in the DataList control.

HeaderStyle

Specifies the style for the header in the DataList control.

ItemStyle

Specifies the style for the items in the DataList control.

SelectedItemStyle

Specifies the style for the selected item in the DataList control.

SeparatorStyle

Specifies the style for the separator between the items in the DataList control.

You can also show or hide different parts of the control. The following table lists the properties that control which parts are shown or hidden.

Property

Description

ShowFooter

Shows or hides the footer section of the DataList control.

ShowHeader

Shows or hides the header section of the DataList control.

The display direction of a DataList control can be vertical or horizontal. Set the RepeatDirection property to specify the display direction.

The layout of the DataList control is controlled with the RepeatLayout property. Setting this property to RepeatLayout.Table will display the DataList in a table format, while RepeatLayout.Flow displays the DataList without a table structure.

Caution noteCaution:

This control can be used to display user input, which might include malicious client script. Check any information that is sent from a client for executable script, SQL statements, or other code before displaying it in your application. You can use validation controls to verify user input before displaying the input text in a control. ASP.NET provides an input request validation feature to block script and HTML in user input.

For more information about security, see Securing Standard Controls, How to: Protect Against Script Exploits in a Web Application by Applying HTML Encoding to Strings, and Introduction to Validating User Input in ASP.NET Web Pages.

Example

The following code example demonstrates how to use a DataList control to display a list of items from a data source.

NoteNote:

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 Page Code Model.

Visual Basic

<%@ 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)))
         dt.Columns.Add(New DataColumn("ImageValue", GetType(String)))
 
         ' 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)
            dr(3) = "Image" & i.ToString() & ".jpg"
 
            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
 
   </script>
 
<head runat="server">
    <title>DataList Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           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: <%# DataBinder.Eval(Container.DataItem, "CurrencyValue", "{0:c}") %>

            <br />

            <asp:Image id="ProductImage" AlternateText="Product picture" 
                 ImageUrl='<%# DataBinder.Eval(Container.DataItem, "ImageValue") %>'
                 runat="server"/>

         </ItemTemplate>
 
      </asp:DataList>
 
   </form>
 
</body>
</html>
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" >
   <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)));
         dt.Columns.Add(new DataColumn("ImageValue", typeof(String)));
 
         // 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);
            dr[3] = "Image" + i.ToString() + ".jpg";
 
            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();
         }

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

      <h3>DataList Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           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: <%# DataBinder.Eval(Container.DataItem, "CurrencyValue", "{0:c}") %>

            <br />

            <asp:Image id="ProductImage" AlternateText="Product picture" 
                 ImageUrl='<%# DataBinder.Eval(Container.DataItem, "ImageValue") %>'
                 runat="server"/>

         </ItemTemplate>
 
      </asp:DataList>
 
   </form>
 
</body>
</html>
.NET Framework Security
Inheritance Hierarchy
System.Object
   System.Web.UI.Control
     System.Web.UI.WebControls.WebControl
       System.Web.UI.WebControls.BaseDataList
        System.Web.UI.WebControls.DataList
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Platforms

Windows 98, Windows Server 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

Version Information

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0
See Also