Row Merging Grid view

For rowIndex As Integer = GridView01.Rows.Count - 2 To 0 Step -1
        Dim gvRow As GridViewRow = GridView01.Rows(rowIndex)
        Dim gvPreviousRow As GridViewRow = GridView01.Rows(rowIndex + 1)
       For cellCount As Integer = 0 To gvRow.Cells.Count - 1
          If gvRow.Cells(cellCount).Text = gvPreviousRow.Cells(cellCount).Text Then
              If gvPreviousRow.Cells(cellCount).RowSpan < 2 Then
                   gvRow.Cells(cellCount).RowSpan = 2
              Else
                 gvRow.Cells(cellCount).RowSpan = gvPreviousRow.Cells(cellCount).RowSpan + 1
              End If
                gvPreviousRow.Cells(cellCount).Visible = False
            End If
        Next
    Next