download datatable as a csv file - asp.net

Question

Hi all I am trying to allow the user to download data from a database so they can manipulate it with out having access to the database. so far I have this it makes the file but I need it to download to the client pc. Any tips?
Protected Sub ExportDataTableToCSV(cmdText As String)
Try
Dim sqlcon_Local As New SqlClient.SqlConnection
sqlcon_Local.ConnectionString = ConfigurationManager.ConnectionStrings("Portal").ConnectionString
Dim objCmd As New SqlCommand(cmdText, sqlcon_Local)
Dim da As SqlDataAdapter = New SqlDataAdapter(objCmd)
Dim dt As DataTable = New DataTable
da.Fill(dt)
Dim filename As String = Server.MapPath("~/download.csv")
Dim sw As New StreamWriter(filename, False)
Dim iColCount As Integer = dt.Columns.Count
For i As Integer = 0 To iColCount - 1
sw.Write(dt.Columns(i))
If i < iColCount - 1 Then
sw.Write(",")
End If
Next
sw.Write(sw.NewLine)
For Each dr As DataRow In dt.Rows
For i As Integer = 0 To iColCount - 1
If Not Convert.IsDBNull(dr(i)) Then
sw.Write(dr(i).ToString())
End If
If i < iColCount - 1 Then
sw.Write(",")
End If
Next
sw.Write(sw.NewLine)
Next
sw.Close()
Response.Clear()
Response.ContentType = "application/csv"
Response.AddHeader("Content-Disposition", "attachment; filename=download.csv")
Response.WriteFile(filename)
Response.Flush()
Response.End()
Catch ex As Exception
End Try
End Sub
what am I doing wrong?
any input will be welcome.
Thanks for your time!

Answer 1

please change Response.ContentType as
Response.ContentType = "text/csv";
hope this will help you

Answer 2

Public Shared Function Export_CSV(ByVal cmdText As String) As String
Dim message As String = Nothing
Try
Dim sqlcon_Local As New SqlClient.SqlConnection
sqlcon_Local.ConnectionString = ConfigurationManager.ConnectionStrings("Portal").ConnectionString
Dim objCmd As New SqlCommand(cmdText, sqlcon_Local)
Dim da As SqlDataAdapter = New SqlDataAdapter(objCmd)
Dim dt As DataTable = New DataTable
da.Fill(dt)
Dim context As HttpContext = HttpContext.Current
context.Response.Clear()
For Each column As DataColumn In dt.Columns
context.Response.Write(column.ColumnName + ",")
Next
context.Response.Write(Environment.NewLine)
For Each row As DataRow In dt.Rows
For i As Integer = 0 To dt.Columns.Count - 1
context.Response.Write(row(i).ToString.Replace(",", String.Empty) + ",")
Next
context.Response.Write(Environment.NewLine)
Next
context.Response.ContentType = "txt/csv"
context.Response.AppendHeader("Content-Disposition", "attachment; filename=" + download + ".csv")
HttpContext.Current.ApplicationInstance.CompleteRequest()
message = "Export Successful"
Catch ex As Exception
message = ex.Message.ToString
End Try
Return message
End Function
ref : http://www.thewebbureau.com/tech_blog/post/Export-DataTable-To-CSV.aspx
If you have problem with IE browser
change
context.Response.AppendHeader("Content-Disposition", "attachment; filename=" + download + ".csv")
to
context.Response.AppendHeader("Content-Disposition", "attachment; inline=" + download + ".csv")