ช่วยดูโค้ดการดึงค่ามาแสดงใน Gridview พอรันดูการทำงานแล้วขึ้น error

<script runat="server">
    Private Sub form_Load(sender As Object, e As EventArgs)
        Dim objConn As New Data.Odbc.OdbcConnection()
        Dim objCmd As New Data.Odbc.OdbcCommand()
        Dim strConnString As String
        strConnString = "Driver={SQL Server};Server=xxx;Database=yyy;Uid=sa;Pwd=zzzz"
        objConn.ConnectionString = strConnString
        objConn.Open()

        BindData()
    End Sub
    Sub BindData()
        Dim strSQL As String
        Dim objConn As SqlDataSource
        strSQL = "SELECT * FROM Warehouse"

        Dim dtReader As Data.IDbConnection
        objConn = New String(strSQL, objConn)
        dtReader = ObjectDataSourceView.()
        

        dtReader.Close()
        dtReader = Nothing
        
    End Sub
   
    Private Sub GridView_RowDataBound(sender As Object, e As GridViewRowEventArgs)
        '*** StockName ***'
        Dim lblStockName As Label = CType(e.Row.FindControl("lblStockName"), Label)
        If Not IsNothing(lblStockName) Then
            lblStockName.Text = e.Row.DataItem("StockName")
        End If

        '*** ProName ***'
        Dim lblProName As Label = CType(e.Row.FindControl("lblProName"), Label)
        If Not IsNothing(lblProName) Then
            lblProName.Text = e.Row.DataItem("ProName")
        End If

        '*** ProTotal ***'
        Dim lblProTotal As Label = CType(e.Row.FindControl("lblProTotal"), Label)
        If Not IsNothing(lblProTotal) Then
            lblProTotal.Text = e.Row.DataItem("ProTotal")
        End If

        '*** Available ***'
        Dim txtAvailable As TextBox = CType(e.Row.FindControl("txtAvailable"), TextBox)
        If Not IsNothing(txtAvailable) Then
            txtAvailable.Text = e.Row.DataItem("Available")
        End If
    End Sub

</script>