Converting Gridview to DataTable in VB.NET - vb.net

Question

I am using this function to create datatable from gridviews. It works fine with Gridviews with AutoGenerateColumns = False and have boundfields or template fileds. But if I use it with Gridviews with AutoGenerateColumn = True I only get back an empty DataTable. Seems Gridview viewstate has been lost or something. Gridview is binded on PageLoad with If Not IsPostback. I can't think of anything else to make it work. Hope someone can help me.
Thanks,
Public Shared Function GridviewToDataTable(gv As GridView) As DataTable
Dim dt As New DataTable
For Each col As DataControlField In gv.Columns
dt.Columns.Add(col.HeaderText)
Next
For Each row As GridViewRow In gv.Rows
Dim nrow As DataRow = dt.NewRow
Dim z As Integer = 0
For Each col As DataControlField In gv.Columns
nrow(z) = row.Cells(z).Text.Replace(" ", "")
z += 1
Next
dt.Rows.Add(nrow)
Next
Return dt
End Function

Answer 1

Slight modification to your function above. If the autogenerate delete, edit or select button flags are set, the values for the fields are offset by one. The following code accounts for that:
Public Shared Function GridviewToDataTable(ByVal PassedGridView As GridView, ByRef Error_Message As String) As DataTable
'-----------------------------------------------
'Dim Tbl_StackSheets = New Data.DataTable
'Tbl_StackSheets = ReportsCommonClass.GridviewToDataTable(StackSheetsGridView)
'-----------------------------------------------
Dim dt As New DataTable
Dim ColInd As Integer = 0
Dim ValOffset As Integer
Try
For Each col As DataControlField In PassedGridView.Columns
dt.Columns.Add(col.HeaderText)
Next
If (PassedGridView.AutoGenerateDeleteButton Or PassedGridView.AutoGenerateEditButton Or PassedGridView.AutoGenerateSelectButton) Then
ValOffset = 1
Else
ValOffset = 0
End If
For Each row As GridViewRow In PassedGridView.Rows
Dim NewDataRow As DataRow = dt.NewRow
ColInd = 0
For Each col As DataControlField In PassedGridView.Columns
NewDataRow(ColInd) = row.Cells(ColInd + ValOffset).Text.Replace(" ", "")
ColInd += 1
Next
dt.Rows.Add(NewDataRow)
Next
Error_Message = Nothing
Catch ex As Exception
Error_Message = "GridviewToDataTable: " & ex.Message
End Try
Return dt
End Function