PrintPreview Problem

[Mangore]

This code is to print Text and it work with me by print a text, but it didn't work with PrintPreview

Imports System.Drawing.Printing

   Private Sub PrintText(ByVal sender As Object, ByVal ev As PrintPageEventArgs)
   ev.Graphics.DrawString(TextBox1.Text, New Font("Arial", 11, FontStyle.Regular), Brushes.Black, 120, 120)
   End Sub

'Print
AddHandler PrintDoc.PrintPage, AddressOf Me.PrintText
PrintDoc.Print() 'print text

'PrintPreview
PrintPreviewDialog1.Document = PrintDoc
PrintPreviewDialog1.ShowDialog()