C++打印机不想打印

Question

我的代码有错误。我的名为“XP-58”的打印机不打印来自 C++ 程序的文本。但是当我从记事本运行打印时，它可以正常工作。我的 C++ 代码

int _tmain(int argc, _TCHAR* argv[])
{
    LPTSTR printerName = (LPTSTR)_T("XP-58");
    CString str = "la-la-la";
    LPBYTE pByte = new BYTE[str.GetLength() + 1];
    memcpy(pByte, (VOID*)LPCTSTR(str), str.GetLength());
    DWORD count = 7;
    BOOL result = RawDataToPrinter(printerName, pByte, count);
    std::cout << result << std::endl;
    system("pause");
    return 0;
}

我使用这里的函数 https://msdn.microsoft.com/en-us/library/windows/desktop/dd162959(v=vs.85).aspx

如您所见，我在程序结束后得到结果“std::cout << result << std::endl;”结果总是显示“1”。

问题是什么？可能我需要为打印机设置指定端口？我的打印机连接到 USB002 端口。当我从记事本开始打印时，我在“打印队列管理器”中看到了这个端口，但是当从我的程序添加任务时，我在管理器中看不到任何端口。请帮忙)

完整代码

#include "stdafx.h"
#include <Windows.h>
#include <Winspool.h>
#include <CommDlg.h>
#include <math.h>
#include <atlstr.h>
#include <iostream>


BOOL RawDataToPrinter(LPTSTR szPrinterName, LPBYTE lpData, DWORD dwCount)
{
    BOOL     bStatus = FALSE;
    HANDLE     hPrinter = NULL;
    DOC_INFO_1 DocInfo;
    DWORD      dwJob = 0L;
    DWORD      dwBytesWritten = 0L;

    // Open a handle to the printer. 
    bStatus = OpenPrinter( szPrinterName, &hPrinter, NULL );
    if (bStatus) {
        // Fill in the structure with info about this "document." 
        DocInfo.pDocName = (LPTSTR)_T("chargebox barcode check");
        DocInfo.pOutputFile = NULL;
        DocInfo.pDatatype = (LPTSTR)_T("RAW");

        // Inform the spooler the document is beginning. 
        dwJob = StartDocPrinter( hPrinter, 1, (LPBYTE)&DocInfo );
        if (dwJob > 0) {
            // Start a page. 
            bStatus = StartPagePrinter( hPrinter );
            if (bStatus) {
                // Send the data to the printer. 
                bStatus = WritePrinter( hPrinter, lpData, dwCount, &dwBytesWritten);
                EndPagePrinter (hPrinter);
            }
            // Inform the spooler that the document is ending. 
            EndDocPrinter( hPrinter );
        }
        // Close the printer handle. 
        ClosePrinter( hPrinter );
    }
    // Check to see if correct number of bytes were written. 
    if (!bStatus || (dwBytesWritten != dwCount)) {
        bStatus = FALSE;
    } else {
        bStatus = TRUE;
    }
    return bStatus;
}


int _tmain(int argc, _TCHAR* argv[])
{
    LPTSTR printerName = (LPTSTR)_T("XP-58");
    CStringW str = L"unicode";
    int bytelen = 2 * str.GetLength();
    LPBYTE pByte = new BYTE[bytelen];
    memcpy(pByte, str, bytelen);
    DWORD count = bytelen;
    BOOL result = RawDataToPrinter(printerName, pByte, count);
    std::cout << GetLastError() << std::endl;
    std::cout << result << std::endl;
    system("pause");
    return(0);
}

Answer 1

打印机不知道您已发送完所有内容，因此不会打印。

要结束一行，您需要在字符串中添加字符"\r\n"。

当您完成一个页面时，将 "\f" 添加到字符串中。