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BaseDataList.DataSource Property

Definition

Gets or sets the source containing a list of values used to populate the items within the control.

public:
 virtual property System::Object ^ DataSource { System::Object ^ get(); void set(System::Object ^ value); };
[System.ComponentModel.Bindable(true)]
public virtual object DataSource { get; set; }
[System.ComponentModel.Bindable(true)]
[System.Web.UI.Themeable(false)]
public virtual object DataSource { get; set; }
[<System.ComponentModel.Bindable(true)>]
member this.DataSource : obj with get, set
[<System.ComponentModel.Bindable(true)>]
[<System.Web.UI.Themeable(false)>]
member this.DataSource : obj with get, set
Public Overridable Property DataSource As Object

Property Value

An IEnumerable or IListSource that contains a collection of values used to supply data to this control. The default value is null.

Attributes

Exceptions

The data source cannot be resolved because a value is specified for both the DataSource property and the DataSourceID property.

The data source is of an invalid type. The data source must be null or implement either the IEnumerable or the IListSource interface.

Examples

The following code example demonstrates how to use the DataSource property to specify the data source 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" >
   <script language="C#" runat="server">
 
      ICollection CreateDataSource() 
      {
         DataTable dt = new DataTable();
         DataRow dr;
 
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
 
         for (int i = 0; i < 9; i++) 
         {
            dr = dt.NewRow();
 
            dr[0] = i;
            dr[1] = "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) 
      {
 
         if (!IsPostBack) 
         {
            // Load this data only once.
            ItemsGrid.DataSource= CreateDataSource();
            ItemsGrid.DataBind();
         }
      }
 
   </script>
 
<head runat="server">
    <title>DataGrid Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid Example</h3>
 
      <b>Product List</b>
 
      <asp:DataGrid id="ItemsGrid"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           AutoGenerateColumns="true"
           runat="server">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle> 
 
      </asp:DataGrid>
 
   </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 language="VB" runat="server">
     Function CreateDataSource() As ICollection
        Dim dt As New DataTable()
        Dim dr As DataRow
        
        dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
        dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
        dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
        
        Dim i As Integer
        For i = 0 To 8
            dr = dt.NewRow()
            
            dr(0) = i
            dr(1) = "Item " + i.ToString()
            dr(2) = 1.23 *(i + 1)
            
            dt.Rows.Add(dr)
        Next i
        
        Dim dv As New DataView(dt)
        Return dv
    End Function 'CreateDataSource


    Sub Page_Load(sender As Object, e As EventArgs)
        
        If Not IsPostBack Then
            ' Load this data only once.
            ItemsGrid.DataSource = CreateDataSource()
            ItemsGrid.DataBind()
        End If
    End Sub 'Page_Load
 
  </script>
 
<head runat="server">
    <title>DataGrid Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid Example</h3>
 
      <b>Product List</b>
 
      <asp:DataGrid id="ItemsGrid"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           AutoGenerateColumns="true"
           runat="server">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle> 
 
      </asp:DataGrid>
 
   </form>
 
</body>
</html>

Remarks

Use the DataSource property to specify the source of values to bind to a data listing control. A data source must be a collection that implements either the System.Collections.IEnumerable interface (such as System.Data.DataView, System.Collections.ArrayList, or System.Collections.Generic.List<T>) or the IListSource interface to bind to a control derived from the BaseDataList class. When you set the DataSource property, you must manually write the code to perform data binding.

If the data source specified by the DataSource property contains multiple sources of data, use the DataMember property to specify the specific source to bind to the control. For example, if you have a System.Data.DataSet object with multiple tables, you must specify which table to bind to the control. After you have specified the data source, use the DataBind method to bind the data source to the control.

Alternately, you can use the DataSourceID property to automatically bind to a data source represented by a data source control. When you set the DataSourceID property, the data listing control automatically binds to the specified data source control. You do not need to write code that explicitly calls the DataBind method.

If values are specified for both the DataSource property and the DataSourceID property, ASP.NET is not able to resolve the data source and an System.Web.HttpException exception is thrown.

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

Applies to

See also