HELP! GridView Sorting at Runtime

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ASP.NET

Hi Guys,

I have a grid that binds the data at runtime...

Dim myCommand = New SqlCommand(strSql, myConnection)
Dim dr As SqlDataReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection)

gvLiveCourses.Visible = True
gvLiveCourses.DataSourceID = ""
gvLiveCourses.DataSource = dr
gvLiveCourses.DataBind()

Next is the OnSort event and function. Actually I just copied it from other forums.

Sub gvLiveCourses_Sorting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewSortEventArgs) 'Handles gvLiveCourses.Sorting
    Dim m_DataTable As DataTable = TryCast(gvLiveCourses.DataSource, DataTable)
    If m_DataTable IsNot Nothing Then
        Dim m_DataView As New DataView(m_DataTable)
        m_DataView.Sort = e.SortExpression + " " & ConvertSortDirectionToSql(e.SortDirection)
        gvLiveCourses.DataSource = m_DataView
        gvLiveCourses.DataBind()
    End If
End Sub
Function ConvertSortDirectionToSql(ByVal sortDirection As SortDirection)
    Dim newSortDirection As String = String.Empty
    Select Case (sortDirection)
        Case sortDirection.Ascending
            newSortDirection = "ASC"
        Case sortDirection.Descending
            newSortDirection = "DESC"
    End Select
    Return newSortDirection
End Function

Now, when I click on the gridview columns it doesn't sort. And when I traced it using breakpoints, I found out that the m_DataTable is empty. But how come this becomes empty since the grid displays the data. I don't get it.

Please let me know on how to correct this code. I am using sqldatareader most of my applications, and I need to add sorting feature on every gridview. There's no problem in the gridview, only the sort feature that has to be added.

I hope you could give me a sample on sorting the gridview using sqldatareader that binds the data at runtime.


Thanks

Hifiger