From MSDN:

SelPrint Method Example
This example prints the formatted text in a RichTextBox control. To try this example, put a RichTextBox control, a CommonDialog control, and a CommandButton control on a form. Paste this code into the Click event of the CommandButton control. Then run the example.
Code:
Private Sub Command1_Click()
   CommonDialog1.Flags = cdlPDReturnDC + cdlPDNoPageNums
   If RichTextBox1.SelLength = 0 Then
      CommonDialog1.Flags = CommonDialog1.Flags + cdlPDAllPages
   Else
      CommonDialog1.Flags = CommonDialog1.Flags + cdlPDSelection
   End If
   CommonDialog1.ShowPrinter
   Printer.Print ""
   RichTextBox1.SelPrint CommonDialog1.hDC
End Sub

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Mark Sreeves
Analyst Programmer

[email protected]
A BMW Group Company