BaseDataList.DataMember 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 or sets the specific data member in a multimember data source to bind to a data listing control.

public:
 property System::String ^ DataMember { System::String ^ get(); void set(System::String ^ value); };

public string DataMember { get; set; }

[System.Web.UI.Themeable(false)]
public string DataMember { get; set; }

member this.DataMember : string with get, set

[<System.Web.UI.Themeable(false)>]
member this.DataMember : string with get, set

Public Property DataMember As String

Property Value

String

A data member from a multimember data source. The default value is Empty.

Attributes: ThemeableAttribute

Examples

The following code example demonstrates how to use the DataMember property to specify which table in a DataSet object to bind to a DataGrid control.


<%@ 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 runat="server">
    <title> BaseDataList DataMember Example </title>
<script runat="server">

      // Create sample data for the DataGrid control with two tables, 
      // Employee and Customer.
      DataSet CreateDataSet()
      {
    
         // Create a table to store employee values.
         DataTable EmployeeTable = new DataTable("Employee");
         DataRow TempDataRow;
   
         // Define the columns for the Employee table.
         EmployeeTable.Columns.Add(
            new DataColumn("EmployeeName", typeof(string)));
         EmployeeTable.Columns.Add(
            new DataColumn("EmployeeID", typeof(int)));

         // Populate the Employee table.
         for (int i=1; i<=5; i++) 
         {
            TempDataRow = EmployeeTable.NewRow();
            TempDataRow[0] = "Employee " + i.ToString();
            TempDataRow[1] = (i+1700);

            EmployeeTable.Rows.Add(TempDataRow);
         }

         // Create a table to store customer values.
         DataTable CustomerTable = new DataTable("Customer");

         // Define the columns for the Customer table.
         CustomerTable.Columns.Add(
            new DataColumn("CustomerName", typeof(string)));
         CustomerTable.Columns.Add(
            new DataColumn("CustomerID", typeof(int)));

         // Populate the Customer table.
         for (int i=1; i<=5; i++) 
         {
            TempDataRow = CustomerTable.NewRow();
            TempDataRow[0] = "Customer " + i.ToString();
            TempDataRow[1] = (i+1700);

            CustomerTable.Rows.Add(TempDataRow);
         }

         // Create a DataSet and add the Employee and Customer tables.
         DataSet ds = new DataSet();
         ds.Tables.Add(EmployeeTable);
         ds.Tables.Add(CustomerTable);

         return ds;

      }
             
      void Page_Load(Object sender, EventArgs e) 
      {

         // The data source only needs to be bound to the DataList  
         // control the first time the page is accessed.    
         if(!IsPostBack)
         {

            // Create the sample data for the DataList control.
            ItemsGrid.DataSource = CreateDataSet();

            // The data source in this example contains multiple tables. 
            // Specify which table to display in the DataList control. 
            ItemsGrid.DataMember = "Customer";

            // Bind the data source to the control.
            ItemsGrid.DataBind();

         }

      }

      void Index_Change(Object sender, EventArgs e) 
      {

         // Create the sample data for the DataList control.
         ItemsGrid.DataSource = CreateDataSet();

         // The data source in this example contains multiple tables. 
         // Specify which table to display in the DataList control 
         // based on the user's selection from the DropDownList control. 
         ItemsGrid.DataMember = SourceList.SelectedItem.Text;

         // Bind the data source to the control. 
         ItemsGrid.DataBind();

      }

   </script>

</head>
<body>

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

      <h3> BaseDataList DataMember Example </h3>
      
      <asp:DataGrid id="ItemsGrid"
           AutoGenerateColumns="True" 
           runat="server">

         <headerstyle backcolor="#00aaaa"/>
</asp:DataGrid>

      <br /><br />

      Select the data source: <br />

      <asp:DropDownList id="SourceList"
           AutoPostBack="True"
           OnSelectedIndexChanged="Index_Change"
           runat="server">

         <asp:Listitem Selected="True">Customer</asp:Listitem>
         <asp:Listitem>Employee</asp:Listitem>

      </asp:DropDownList>

   </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 runat="server">
    <title> BaseDataList DataMember Example </title>
<script runat="server">

      ' Create sample data for the DataGrid control with two tables,
      ' Employee and Customer.
      Function CreateDataSet() As DataSet
    
         ' Create a table to store employee values.
         Dim EmployeeTable As DataTable = New DataTable("Employee")
         Dim TempDataRow As DataRow
   
         ' Define the columns for the Employee table.
         EmployeeTable.Columns.Add( _
            New DataColumn("EmployeeName", GetType(String)))
         EmployeeTable.Columns.Add( _
            New DataColumn("EmployeeID", GetType(Integer)))

         ' Populate the Employee table.
         Dim i As Integer

         For i=1 To 5 
         
            TempDataRow = EmployeeTable.NewRow()
            TempDataRow(0) = "Employee " & i.ToString()
            TempDataRow(1) = (i+1700)

            EmployeeTable.Rows.Add(TempDataRow)

         Next

         ' Create a table to store customer values.
         Dim CustomerTable As DataTable = New DataTable("Customer")

         ' Define the columns for the Customer table.
         CustomerTable.Columns.Add( _
            New DataColumn("CustomerName", GetType(String)))
         CustomerTable.Columns.Add( _
            New DataColumn("CustomerID", GetType(Integer)))

         ' Populate the Customer table.
         For i=1 To 5  

            TempDataRow = CustomerTable.NewRow()
            TempDataRow(0) = "Customer " & i.ToString()
            TempDataRow(1) = (i+1700)

            CustomerTable.Rows.Add(TempDataRow)
         
         Next

         ' Create a DataSet and add the Employee and Customer tables.
         Dim ds As DataSet = New DataSet()
         ds.Tables.Add(EmployeeTable)
         ds.Tables.Add(CustomerTable)

         Return ds

      End Function
             
      Sub Page_Load(sender As Object, e As EventArgs) 

         ' The data source only needs to be bound to the DataList  
         ' control the first time the page is accessed.    
         If Not IsPostBack Then

            ' Create the sample data for the DataList control.
            ItemsGrid.DataSource = CreateDataSet()

            ' The data source in this example contains multiple tables.  
            ' Specify which table to display in the DataList control. 
            ItemsGrid.DataMember = "Customer"

            ' Bind the data source to the control.
            ItemsGrid.DataBind()

         End If

      End Sub

      Sub Index_Change(sender As Object, e As EventArgs) 

         ' Create the sample data for the DataList control.
         ItemsGrid.DataSource = CreateDataSet()

         ' The data source in this example contains multiple tables. 
         ' Specify which table to display in the DataList control 
         ' based on the user's selection from the DropDownList control. 
         ItemsGrid.DataMember = SourceList.SelectedItem.Text

         ' Bind the data source to the control. 
         ItemsGrid.DataBind()

      End Sub

   </script>

</head>
<body>

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

      <h3> BaseDataList DataMember Example </h3>
      
      <asp:DataGrid id="ItemsGrid"
           AutoGenerateColumns="True" 
           runat="server">

         <headerstyle backcolor="#00aaaa"/>
</asp:DataGrid>

      <br /><br />

      Select the data source: <br />

      <asp:DropDownList id="SourceList"
           AutoPostBack="True"
           OnSelectedIndexChanged="Index_Change"
           runat="server">

         <asp:Listitem Selected="True">Customer</asp:Listitem>
         <asp:Listitem>Employee</asp:Listitem>

      </asp:DropDownList>

   </form>
 
</body>

</html>

Remarks

Use the DataMember property to specify a member from a multimember data source to bind to the list control. For example, if you have a data source with more than one table specified in the DataSource property, use the DataMember property to specify which table to bind to a data listing control.

This property cannot be set by themes or style sheet themes. For more information, see ThemeableAttribute and ASP.NET Themes and Skins.

Applies to

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