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SqlDataSource.DataSourceMode Property

  • Reference

Definition

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

Gets or sets the data retrieval mode that the SqlDataSource control uses to fetch data.

public:
 property System::Web::UI::WebControls::SqlDataSourceMode DataSourceMode { System::Web::UI::WebControls::SqlDataSourceMode get(); void set(System::Web::UI::WebControls::SqlDataSourceMode value); };
public System.Web.UI.WebControls.SqlDataSourceMode DataSourceMode { get; set; }
member this.DataSourceMode : System.Web.UI.WebControls.SqlDataSourceMode with get, set
Public Property DataSourceMode As SqlDataSourceMode

Property Value

SqlDataSourceMode

One of the SqlDataSourceMode values. The default is the DataSet value.

Exceptions

ArgumentOutOfRangeException

The DataSourceMode property is not one of the values defined in the SqlDataSourceMode.

Examples

The following code example demonstrates how to set the DataSourceMode property of the SqlDataSource control to the DataReader value for a scenario with a ListBox control that requires no sorting, paging, nor filtering.

<%@ Page language="C#" %>

<!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>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">
      <asp:SqlDataSource
          id="SqlDataSource1"
          runat="server"
          DataSourceMode="DataReader"
          ConnectionString="<%$ ConnectionStrings:MyNorthwind%>"
          SelectCommand="SELECT LastName FROM Employees">
      </asp:SqlDataSource>

      <asp:ListBox
          id="ListBox1"
          runat="server"
          DataTextField="LastName"
          DataSourceID="SqlDataSource1">
      </asp:ListBox>

    </form>
  </body>
</html>

<%@ Page language="VB" %>

<!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>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">
      <asp:SqlDataSource
          id="SqlDataSource1"
          runat="server"
          DataSourceMode="DataReader"
          ConnectionString="<%$ ConnectionStrings:MyNorthwind%>"
          SelectCommand="SELECT LastName FROM Employees">
      </asp:SqlDataSource>

      <asp:ListBox
          id="ListBox1"
          runat="server"
          DataTextField="LastName"
          DataSourceID="SqlDataSource1">
      </asp:ListBox>

    </form>
  </body>
</html>

Remarks

The data retrieval mode identifies how a SqlDataSource control retrieves data from the underlying database.

When the DataSourceMode property is set to the DataSet value, data is loaded into a DataSet object and stored in memory on the server. This enables scenarios where user interface controls, such as GridView, offer sorting, filtering, and paging capabilities.

When the DataSourceMode property is set to the DataReader value, data is retrieved by a IDataReader object, which is a forward-only, read-only cursor. The specific type of the IDataReader object depends on the NET data provider that the SqlDataSource uses, which is identified by the ProviderName property. By default, the SqlDataSource control uses the provider for Microsoft SQL Server, the System.Data.SqlClient, and the data reader is a SqlDataReader object.

If you change the DataSourceMode property, the DataSourceChanged event is raised, causing any controls that are bound to the SqlDataSource to rebind.

The value of the DataSourceMode property is stored in view state.

Applies to

See also