Visual Basic

Public Sub WriteCsv(dt as datatable, filename as string, delimiter as char)

     dim writer as System.IO.StreamWriter

     try
          writer = new System.IO.StreamWriter(filename)

          'write the column names
          for i as integer = 0 to dt.Columns.Count - 1
               writer.write(dt.Columns(i).ColumnName)
               if i <> dt.Columns.Count - 1 then writer.write (delimiter)
          next

          writer.write(controlchars.newline)

          'write the data
          For i As Integer = 0 To dt.Rows.Count - 1
               For j As Integer = 0 To dt.Columns.Count - 1
                    writer.Write(dt.Rows(i).Item(j))
                    If j <> dt.Columns.Count - 1 Then writer.Write(delimiter)
               Next
               if i <> dt.Rows.Count - 1 then writer.Write(ControlChars.NewLine)
          Next

          writer.Flush()
          writer.Close()
          writer = Nothing
     Catch ex As Exception
          If Not writer Is Nothing Then
               writer = Nothing
          End If
    End Try
End Sub

Thread Safety
Public static (Shared in Visual Basic) members of this type are safe for multithreaded
operations. Instance members are not guaranteed to be thread-safe.
 
This implementation does not provide a synchronized (thread-safe) wrapper for an Array;
however, .NET Framework classes based on Array provide their own synchronized version of the
collection using the SyncRoot property.
 
Enumerating through a collection is intrinsically not a thread-safe procedure. Even when a
collection is synchronized, other threads could still modify the collection, which causes the
enumerator to throw an exception. To guarantee thread safety during enumeration, you can either
lock the collection during the entire enumeration or catch the exceptions resulting from changes
made by other threads.