Public Class Form1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim strPDFFile As String = Dir("d:\Test.pdf")
Dim PrintPDFFile As New ProcessStartInfo

Do Until strPDFFile Is Nothing
PrintPDFFile.UseShellExecute = True
PrintPDFFile.Verb = "print"
PrintPDFFile.WindowStyle = ProcessWindowStyle.Hidden
PrintPDFFile.FileName = strPDFFile
Process.Start(PrintPDFFile)
strPDFFile = Dir()
Loop

End Sub
End Class

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