Retreive data from sql database,bind it in grid and display it in excel sheet

Am trying with the following code to retrieve data from sql server, followed by binding it in datagrid and finally output is displaying in excel sheet.

No errors! But not getting output. Help me out.

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim con = obj_connection_string.getSQLConnection()
If con.State = ConnectionState.Open Then
con.Close()
End If
con.Open()
Dim cmd As New SqlCommand()
cmd.CommandText = "select username,password,isactive from tbl_Login_Details "
cmd.Connection = con
da.SelectCommand = cmd
da.Fill(ds)
cmd.ExecuteNonQuery()
Grid.DataSource = ds
Grid.DataBind()
End Sub

Protected Sub btnSubmit_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSubmit.Click
Response.Clear()
Response.AddHeader("content-disposition", "attachment;filename=FileName.xls")

Response.Charset = ""

Response.Cache.SetCacheability(HttpCacheability.NoCache)

Response.ContentType = "application/vnd.xls"

Dim stringWrite As New System.IO.StringWriter()

Dim htmlWrite As System.Web.UI.HtmlTextWriter = New HtmlTextWriter(stringWrite)

Grid.RenderControl(htmlWrite)

Response.Write(stringWrite.ToString())

Response.Close()
End Sub

Tags: Visual Basic, SQL, ASP.NET, Microsoft Excel, DataGrid