Sub btnExport_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnExport.Click
         '## Definitions ## 
        Dim strOF As String
        Protected WithEvents txtExportPath As System.Web.UI.WebControls.TextBox


         '## Code ## 
        strOF = txtExportPath.Text
         'strOF = "d:\test\of.txt" 
        objSW = New StreamWriter(strOF, False)

..................................
End Sub