how to write logic for gridview sorting ?

Question

hello How to write a logic that will perofrm the sorting operation gridview. using N-Tier application? Thanking and regards

James Tomar · Answer

Protected Sub GridView1_Sorting( ByVal sender As Object  ByVal e As System.Web.UI.WebControls.GridViewSortEventArgs) Handles GridView1.Sorting GridViewSortExpression = e.SortExpression Dim pageIndex As Integer = GridView1.PageIndex GridView1.DataSource = SortDataTable(GridView1.DataSource False ) GridView1.DataBind() GridView1.PageIndex = pageIndex End Sub Protected Sub GridView1_PageIndexChanging( ByVal sender As Object  ByVal e As System.Web.UI.WebControls.GridViewPageEventArgs) Handles GridView1.PageIndexChanging GridView1.DataSource = SortDataTable(GridView1.DataSource True ) GridView1.PageIndex = e.NewPageIndex GridView1.DataBind() End Sub 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 Function SortDataTable( ByVal dataTable As DataTable ByVal isPageIndexChanging As Boolean ) As DataView If Not dataTable Is Nothing Then Dim dataView As New DataView(dataTable) If GridViewSortExpression String .Empty Then If isPageIndexChanging Then dataView.Sort = String .Format( {0} {1}  GridViewSortExpression GridViewSortDirection) Else dataView.Sort = String .Format( {0} {1}  GridViewSortExpression GetSortDirection()) End If End If Return dataView Else Return New DataView() End If End Function