ObjectDataSource.SortParameterName Property
Gets or sets the name of the business object that the SelectMethod parameter used to specify a sort expression for data source sorting support.
Assembly: System.Web (in System.Web.dll)
Property Value
Type: System.StringThe name of the method parameter used to indicate the parameter which is used to sort the data. The default is an empty string.
The SortParameterName property is used to support data source sorting. When a SortExpression property is set on the DataSourceSelectArguments object and passed to the Select method, the SortParameterName value identifies the parameter name of the SelectMethod business object method according to which the data is sorted.
If the ObjectDataSource is associated with a data-bound control, the values that are passed to this parameter take the form of comma-separated field values followed by "ASC" or "DESC". For example, the value for an ascending sort on Name would be "Name ASC".
The SortParameterName property delegates to the SortParameterName property of the ObjectDataSourceView object that is associated with the ObjectDataSource control.
This section contains two code examples. The first code example demonstrates how to implement a type that supports sorting. The second code example demonstrates how to implement a sort expression.
The following code example demonstrates how to implement a type that supports sorting. The SelectMethod of the SortingData class takes a parameter, sortExpression. The string that is passed to SelectMethod is used for the Sort property of the DataView object that is returned by SelectMethod.
Imports System Imports System.Data Imports System.Configuration Imports System.Web Imports System.Web.Security Imports System.Web.UI Imports System.Web.UI.WebControls Imports System.Web.UI.WebControls.WebParts Imports System.Web.UI.HtmlControls Namespace Samples.AspNet.VB Public Class SortingData Public Sub New() End Sub Private Shared table As DataTable Private Function CreateData() As DataTable table = New DataTable() table.Columns.Add("Name", GetType(String)) table.Columns.Add("Number", GetType(Integer)) table.Rows.Add(New Object() {"one", 1}) table.Rows.Add(New Object() {"two", 2}) table.Rows.Add(New Object() {"three", 3}) table.Rows.Add(New Object() {"four", 4}) Return table End Function Public Function SelectMethod(ByVal sortExpression As String) As DataView If table Is Nothing Then table = CreateData() End If Dim dv As New DataView(table) dv.Sort = sortExpression Return dv End Function End Class End Namespace
The following code example demonstrates how to implement a sort expression. The code in the Web page creates an instance of the ObjectDataSource control. The TypeName property is set to SortingData and the SortParameterName property is set to sortExpression. The AllowSorting property of the GridView control is set to true. When the user clicks the Sort button, the field name, Name or Number, is passed to SelectMethod in the sort parameter.
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB" Assembly="Samples.AspNet.VB" %> <%@ Page Language="VB" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head id="Head1" runat="server"> <title>Untitled Page</title> </head> <body> <form id="form1" runat="server"> <div> <asp:GridView ID="GridView1" runat="server" DataSourceID="ObjectDataSource1" AllowSorting="True"> </asp:GridView> <asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="SelectMethod" TypeName="Samples.AspNet.VB.SortingData" SortParameterName="sortExpression"> </asp:ObjectDataSource> </div> </form> </body> </html>
Available since 2.0