[RESOLVED] How to print text to LPT1: with VB.Net 2005

[parminder]

Hi all programmers,


I want to print some text to LPT1: port attached to a Dot Matrix Printer in VB.Net 2005 like
Print "Hello World" to LPT1:


I have done this in VB.Net 2002 using Win32 API and File Stream.
(The link for it is :http://www.vbforums.com/showthread.php?t=253270 )

This cocept is not working in VB.Net 2005. The reason is function
FileStream(intPtr, ...) version is outdated in VB.Net 2005


Can anybody tell me how to do it in VB.Net 2005

Thanks

Parminder

[parminder]

[pax]

I have no idea if this works, but have you tried using the new SafeHandle?

Dim sfh As New Microsoft.Win32.SafeHandles.SafeFileHandle(fh, True)
        Dim fs As IO.FileStream = New IO.FileStream(sfh, IO.FileAccess.ReadWrite)

[gigemboy]

Is there a reason you dont want to use a normal print document and .NET printing methods?

[parminder]

Thanks PAX,

Your code is working.

The Code I used is:

Dim fh As IntPtr
        Dim SW As StreamWriter
        Dim FS As FileStream
        fh = Win32API.CreateFile("LPT1:", Win32API.GENERIC_WRITE, 0, 0, Win32API.CREATE_ALWAYS, 0, 0)
        Dim sfh As New Microsoft.Win32.SafeHandles.SafeFileHandle(fh, True)
        FS = New FileStream(sfh, FileAccess.Write)
        FS.Flush()
        SW = New StreamWriter(FS)
        SW.WriteLine("Simple Text")
        FS.Flush()
        SW.Close()
        FS.Close()
        sfh.Close()

And the support class :

Public Class Win32API
    Public Const GENERIC_WRITE = &H40000000
    Public Const CREATE_ALWAYS = 2
    Public Const OPEN_EXISTING = 3
    Public Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Integer, ByVal dwShareMode As Integer, ByVal lpSecurityAttributes As Integer, ByVal dwCreationDisposition As Integer, ByVal dwFlagsAndAttributes As Integer, ByVal hTemplateFile As Integer) As Integer
    Public Declare Function CloseHandle Lib "kernel32" Alias "CloseHandle" (ByVal hObject As Long) As Long
End Class

Thanks again to Pax

[parminder]

Is there a reason you dont want to use a normal print document and .NET printing methods?

I am sending simple text (escape codes can be used) to different Dot Matrix Printers attached to one machine simultaneously and what text send to which printer is decided by software depending user's inputs. Using this I can use LPT1:,LPT2:,LPT3:, COM1:,COM2:,COM3:,COM4:,... simultaneously
There is not matter which printer is default printer. In fact, this type of printing is driver-independent (for text with optional escape codes for dos style)
This allow me to print one text-set on LPT1: which is near to computer and mean time software is printing second text-set to serial printer attached to COM1: (The distance of second printer from computer is 15 meter)

Even parrerel port LPTn: allow me to print text at distance of 15 feet.

... and it is fast to print text as in DOS style applications.

So the reasons is "Fast, Simulataneous and Printer-driver independent printing"

[michaelrawi]

Hi, Im currently works on a project just like parminder.

Here's my code:

Const a As String = "N" & vbCrLf & _
            "B22,120,0,1,2,0,80,B," & """PUR001MSK200906000""" & vbCrLf & _
            "I8,1,1" & vbCrLf & _
            "A58,68,0,4,1,1,N," & """PT SEKAR BUMI Tbk.""" & vbCrLf & _
            "A159,268,0,4,1,1,N," & """BOX ID""" & vbCrLf & _
            "A76,352,0,4,1,1,N," & """" & vbCrLf & _
            "A76,352,0,4,1,1,N," & """PUR001MSK200906000""" & vbCrLf & _
            "P1"
 
 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim fh As IntPtr
        Dim SW As IO.StreamWriter
        Dim FS As IO.FileStream
        fh = Win32API.CreateFile("LPT1:", Win32API.GENERIC_WRITE, 0, 0, Win32API.CREATE_ALWAYS, 0, 0)
        'This one works fine
        'fh = Win32API.CreateFile("C:\test.txt", Win32API.GENERIC_WRITE, 0, 0, Win32API.CREATE_ALWAYS, 0, 0)
        Dim sfh As New Microsoft.Win32.SafeHandles.SafeFileHandle(fh, True)
        FS = New IO.FileStream(sfh, IO.FileAccess.ReadWrite)
        FS.Flush()
        SW = New IO.StreamWriter(FS)
        SW.WriteLine(a)
        FS.Flush()
        SW.Close()
        FS.Close()
        sfh.Close()
    End Sub

The problem is, I got an error said
ArgumentExepction was unhandled
Invalid handle
Parameter name: handle.

Can someone help me with this problem ?