Gridview To Database Rpoblem?

Hi
I have page where gridview is loaded from the Excel sheet and when the button is clicked it must insert those values in to the table and  ........the code for loading the gridview from the excel if working fine but when i click on the Insert button i am getting the errors the code behind for button is as follows:
  Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
' Dim constr As String = "...." 'your connection string
' Dim connection As SqlConnection = New SqlConnection(constr)
Dim i As Integer
Dim ia As Integer = ds.Tables("table").Rows.Count - 1
For i = 0 To ia
Dim one As String = ds.Tables("table").Rows(i)("Column1")
Dim two As String = ds.Tables("table").Rows(i)("Column2")
Dim three As String = ds.Tables("table").Rows(i)("Column3")
Dim four As String = ds.Tables("table").Rows(i)("Column4")
Dim five As String = ds.Tables("table").Rows(i)("Column5")
Dim six As String = ds.Tables("table").Rows(i)("Column6")
Dim seven As String = ds.Tables("table").Rows(i)("Column7")
Dim eight As String = ds.Tables("table").Rows(i)("Column8")
Dim nine As String = ds.Tables("table").Rows(i)("Column9")
Dim ten As String = ds.Tables("table").Rows(i)("Column10")

'get every cell content of this row like the above line
' Dim sqlsel As String = "insert into table('ID') values('" + one + "')"
Dim cmdSavegrd As OdbcCommand = New OdbcCommand("INSERT INTO gd_master VALUES( " & one & ",'" & two & "', '" & three & "'," & four & ",'" & five & "'," & six & "," & seven & ",'" & eight & "'," & nine & ",'" & ten & "')", con)
'Dim sdc As SqlCommand = New SqlCommand(sqlsel, con)
' sdc.CommandType = CommandType.Text
con.Open()
'sdc.ExecuteNonQuery()
cmdSavegrd.ExecuteReader()
con.Close()

Next
End Sub
  
 
The Error i am getting is as follows .........
"Object reference not set to an instance of an object. "
Please can any help me in this?>?