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If you set AllowPaging=”true” or AllowSorting=”true” on a GridView control without using a DataSourceControl DataSource (i.e. SqlDataSource, ObjectDataSource), you will run into the following errors:

When changing the page on the GridView control:

The GridView ‘GridViewID’ fired event PageIndexChanging which wasn’t handled.

When clicking a column name to sort the column on the GridView control:

The GridView ‘GridViewID’ fired event Sorting which wasn’t handled.

As a result of not setting the DataSourceID property of the GridView to a DataSourceControl DataSource, you have to add event handlers for sorting and paging.
<%@ Page Language=”VB” %>
 
<%@ Import Namespace=”System.Data” %>
<%@ Import Namespace=”System.Data.OleDb” %>
 
<script runat=”server”>   
    Private Sub PopulatePublishersGridView()
        Dim connectionString As String = AccessConnectionString()
        Dim accessConnection As OleDbConnection = New OleDbConnection(connectionString)
 
        Dim sqlQuery As String = “SELECT [PubID], [Name], [Company Name], [Address], [City], [State], [Zip], [Telephone], [Fax], [Comments] FROM Publishers ORDER BY [Name] ASC;”
 
        Dim accessCommand As New OleDbCommand(sqlQuery, accessConnection)
 
        Dim publishersDataAdapter As New OleDbDataAdapter(accessCommand)
        Dim publishersDataTable As New DataTable(“Publishers”)
        publishersDataAdapter.Fill(publishersDataTable)
 
        Dim dataTableRowCount As Integer = publishersDataTable.Rows.Count
 
        If dataTableRowCount > 0 Then
            gridViewPublishers.DataSource = publishersDataTable
            gridViewPublishers.DataBind()
        End If
    End Sub
 
    Private Function AccessConnectionString() As String
        Dim accessDatabasePath As String = Server.MapPath(“~/App_Data/biblio.mdb”)
        Return String.Format(“Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};”, accessDatabasePath)
    End Function
 
    Private Property GridViewSortDirection() As String
        Get
            Return IIf(ViewState(“SortDirection”) = Nothing, “ASC”, ViewState(“SortDirection”))
        End Get
        Set(ByVal value As String)
            ViewState(“SortDirection”) = value
        End Set
    End Property
 
    Private Property GridViewSortExpression() As String
        Get
            Return IIf(ViewState(“SortExpression”) = Nothing, String.Empty, ViewState(“SortExpression”))
        End Get
        Set(ByVal value As String)
            ViewState(“SortExpression”) = value
        End Set
    End Property
 
    Private Function GetSortDirection() As String
        Select Case GridViewSortDirection
            Case “ASC”
                GridViewSortDirection = “DESC”
 
            Case “DESC”
                GridViewSortDirection = “ASC”
        End Select
 
        Return GridViewSortDirection
    End Function
 
    Protected Sub gridViewPublishers_PageIndexChanging(ByVal sender As Object, ByVal e As GridViewPageEventArgs)
        gridViewPublishers.DataSource = SortDataTable(CType(gridViewPublishers.DataSource,DataTable), True)  gridViewPublishers.PageIndex = e.NewPageIndex
        gridViewPublishers.DataBind()
    End Sub
 
    Protected Function SortDataTable(ByVal pdataTable As DataTable, ByVal isPageIndexChanging As Boolean) As DataView
        If Not pdataTable Is Nothing Then
            Dim pdataView As New DataView(pdataTable)
            If GridViewSortExpression <> String.Empty Then
                If isPageIndexChanging Then
                    pdataView.Sort = String.Format(“{0} {1}”, GridViewSortExpression, GridViewSortDirection)
                Else
                    pdataView.Sort = String.Format(“{0} {1}”, GridViewSortExpression, GetSortDirection())
                End If
            End If
            Return pdataView
        Else
            Return New DataView()
        End If
    End Function
 
    Protected Sub gridViewPublishers_Sorting(ByVal sender As Object, ByVal e As GridViewSortEventArgs)
        GridViewSortExpression = e.SortExpression
        Dim pageIndex As Integer = gridViewPublishers.PageIndex
        gridViewPublishers.DataSource =  SortDataTable(CType(gridViewPublishers.DataSource,DataTable), False)
        gridViewPublishers.DataBind()
        gridViewPublishers.PageIndex = pageIndex
    End Sub
 
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        PopulatePublishersGridView()
    End Sub
</script>
 
<!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 id=”Head1″ runat=”server”>
    <title>GridView Sorting/Paging without a DataSourceControl DataSource</title>
</head>
<body>
    <form id=”form” runat=”server”>
        <div>
            <asp:GridView ID=”gridViewPublishers” AllowPaging=”true” AllowSorting=”true” AutoGenerateColumns=”false”
                EmptyDataText=”No records found” PagerSettings-Mode=”NumericFirstLast” PageSize=”25″
                OnPageIndexChanging=”gridViewPublishers_PageIndexChanging” OnSorting=”gridViewPublishers_Sorting”
                runat=”server”>
                <AlternatingRowStyle BackColor=”LightGray” />
                <HeaderStyle BackColor=”Gray” Font-Bold=”true” Font-Names=”Verdana” Font-Size=”Small” />
                <PagerStyle BackColor=”DarkGray” Font-Names=”Verdana” Font-Size=”Small” />
                <RowStyle Font-Names=”Verdana” Font-Size=”Small” />
                <Columns>
                    <asp:BoundField DataField=”PubID” HeaderText=”Publisher ID” SortExpression=”PubID” />
                    <asp:BoundField DataField=”Name” HeaderText=”Name” SortExpression=”Name” />
                    <asp:BoundField DataField=”Company Name” HeaderText=”Company Name” SortExpression=”Company Name” />
                    <asp:BoundField DataField=”Address” HeaderText=”Address” SortExpression=”Address” />
                    <asp:BoundField DataField=”City” HeaderText=”City” SortExpression=”City” />
                    <asp:BoundField DataField=”State” HeaderText=”State” SortExpression=”State” />
                    <asp:BoundField DataField=”Zip” HeaderText=”Zip” SortExpression=”Zip” />
                    <asp:BoundField DataField=”Telephone” HeaderText=”Telephone” SortExpression=”Telephone” />
                    <asp:BoundField DataField=”Fax” HeaderText=”Fax” SortExpression=”Fax” />
                    <asp:BoundField DataField=”Comments” HeaderText=”Comments” SortExpression=”Comments” />
                </Columns>
            </asp:GridView>
        </div>
    </form>
</body>
</html>