Dim path As String = "Program Files\MyTest.csv"
Dim fs As FileStream
If File.Exists(path) = False Then
fs = File.Create(path)
fs.Close()
End If
fs = File.OpenWrite(path)
Dim info As Byte() = _
New UTF8Encoding(True).GetBytes("a,a,a,a,a")
fs.Write(info, 0, info.Length)
fs.Close()