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PrinterCE SDK
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Developer Info
   eVC MFC
   eVC C/C++
   eVB

Special Features
   AsciiCE
   PrintDC
   BarcodeCE

Documentation
   PrinterCE SDK
   AsciiCE
   PrintDC
   BarcodeCE

Special Topics
  Supported Printers
  Bluetooth Printing
  Network Printing
  DLL Load Error

.Net CF C# or VB.Net:
  PrinterCE.NetCF SDK

-----------------------------

Software Developers
  PrinterCE SDK
  PrinterCE.NetCF SDK
  PocketHTMLprint SDK

Printing Utilities
  PrintPocketCE
  PIEprint
  PocketPixPrint
  PocketShot
  PocketClipPrint

 Arcade Games
  SockOut
  MazeCraze

Contact Info

PrinterCE - C++ Installation and Usage

Source Code for PrCEDemo
The source code for the C++ PrinterCE demo program (PrCEDemo) can be downloaded here. This ZIP file includes full source code shared by eVC project files that support Pocket PC, HPC/Pro and 2000. For fully-compiled ready-to-run copies of PrCEDemo, download here. Note that you will need to download and install an evaluation version of PrinterCE prior to using PrCEDemo.

Using PrinterCE in a C++ program
These instructions for installing and using PrinterCE assumes that you are familiar with the steps for creating a C++ program Microsoft's eVC Embedded Visual Tools. The snippet sample code below uses the #import statement to import PrinterCE's type library (which you can download from table above).  The type library provides information needed to access PrinterCE. The project then uses a "Smart Pointer" to handle some of the complexities of working with an ActiveX control such as PrinterCE. The function InitPrinterCE() below looks to see if PrinterCE has been installed and registered. If so, an instance of PrinterCE is created and your app can begin printing.

#include "stdafx.h"
#include <Atlbase.h>

//PrCEUser.h and PrEngineCE.tlb are available for download from the table above
#import "PrEngineCE.tlb" raw_interfaces_only no_namespace
#include "PrCEUser.h" //PrinterCE defs file that defines all user constants

CComQIPtr<IPrinterCE> spPrinterCE;
/*********************************************************
  InitPrinterCE() - Create instances of PrinterCE & BarcodeCE
*********************************************************/
BOOL InitPrinterCE()
{
  CLSID clsid;
  HRESULT hr;

  CoInitializeEx(NULL, COINIT_MULTITHREADED);
  hr=CLSIDFromProgID(_T("PrEngineCE.PrinterCE"),&clsid);
  if (SUCCEEDED(hr)) {
    hr = spPrinterCE.CoCreateInstance(clsid);
  }
  if (FAILED(hr)) {
    MessageBox(NULL,_T("Failed to init PrinterCE"),_T("Init Failed..."),MB_OK);
     return FALSE;
  }
  return TRUE;
}

/*********************************************************
 TestFn() - Simple "Hello World" test function
*********************************************************/
void TestFn() 
{
    if (InitPrinterCE()) {
        / Make sure we have an instance of PrinterCE - "spPrinterCE" is our instance
       spPrinterCE->SelectPrinter();   //Have PrinterCE pop up Select Printer dialog box
       //Send out "Hello World" at default upper left printing position of page
       spPrinterCE->DrawText(_T("Hello World"),NULL,NULL,NULL);
       spPrinterCE->EndDoc();  //Done... print out our "Hello World"
    }
}

C++ Issues
There are some issues that C++ developers must deal with that are unfortunate results of ActiveX controls being designed to work with eVB.

Function Calls
The PrinterCE documentation follows the eVB scheme that “subroutines” (functions that do NOT return a value) do not place parameters within parentheses, while “functions” (which DO return a value) do use parens. Of course, C++ always uses parens. So when the documentation defines the DrawCircle method as: “object.DrawCircle x, y, radius, [color], [ aspect]” the C++ programmer must convert this to : spPrinterCE->DrawCircle(x,y,radius,color,aspect);
 
PrinterCE Properties
The PrinterCE properties must have “get_” or "put_” pre-appended to C++ property functions. For example, the FontBold property is specified in the documentation as: object.FontBold [= Boolean]. An eVB program can set this property by PrinterCE.FontBold=True. A C++ app must call spPrinterCE->put_FontBold(VARIANT_TRUE); Similarly, to get the current X coordinate from PrinterCE, MFC calls xCoord=spPrinterCE->get_TextX();

VARIANT BOOL
Every C++ developer knows that the Boolean value FALSE is 0 and TRUE is 1. But in eVB, TRUE is –1 (although FALSE is still 0). C++ defines the type VT_BOOL for this situation with the values VARIANT_TRUE and VARIANT_FALSE. All PrinterCE functions that expect a Boolean value look for either VARIANT_TRUE or VARIANT_FALSE. Note that PrinterCE functions are designed to work fine with the standard TRUE/FALSE as well as VARIANT_TRUE/VARIANT_FALSE, but any PrinterCE functions that return Boolean values will return the VARIANT versions.

VARIANT Data Types
Certain PrinterCE functions use “optional” parameters. For example, the DrawText method is defined as: “object.DrawText string, [x], [y], [count]” where x, y and count are “optional”. In C++, these sort of optional parameters are handled by overloading functions so that you might have several variants of DrawText() to deal with all possible calls. eVB cannot deal with overloaded functions, so any “optional” parameters must be passed as VARIANT data types. (Please check the Microsoft online documentation for more information on VARIANTs).

Basically, a VARIANT can represent a wide variety of data types including VT_EMPTY. When an eVB program calls a PrinterCE function without one or more of the optional parameters, it eVB automatically passes an “empty” VARIANT for each “omitted” parameter. A C++ program can instead pass NULL (0) for an empty parameter and PrinterCE will work fine. But when the C++ program actually wants to pass a value for one of these optional params, a VARIANT value must be passed. Examples of using VARIANTS are found below.

Wrapping up – a C++ Example
An full ready-to-compile example is worth its weight in gold. The source code for the C++ PrinterCE demo program (PrCEDemo) can be downloaded here. This ZIP file includes full source code shared by eVC project files that support Pocket PC, HPC/Pro and 2000 projects. For fully-compiled ready-to-run copies of PrCEDemo, download here.