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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.

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

'Declaration
Public Property SortParameterName As String

Property Value

Type: System.String
The 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>

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0
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