MFC对话框使用CPrintDialog实现打印，指定打印机、后台打印

推荐下 不错。

对话框打印，网上一搜一大堆，基本分2类：

A类： CPrintDialog.DoModal，然后在模态对话框里选打印机、打印配置；

B类：GetPrinterDeviceDefaults，调用默认打印机。

我的工作内容是理解以上2类后，再根据MSDN，实现MDF对话框后台指定打印机打印。

废话不多说，上菜~

功能：基于对话框的MFC打印（非文档视图结构），指定打印机，后台打印（不弹出对话框）

思路：

1、枚举打印机，并选择其中一个；

2、CPrintDialog实例指定到选中的打印机；

3、CPrintDialog后台打印

具体实现：

1、变量（控件）。在对话框上添加一个combobox（IDC_COMBO1，对应变量m_cboPrint）、一个edit（IDC_EDIT1），edit允许回车，多行（代码就不贴了，知道MFC应该就懂）；

2、在OnInitDialog里枚举打印机设备，如果报函数未定义，加入头文件#include <winspool.h>

需要调用两次EnumPrinters函数，第一次的到结构体的大小，第二次得到打印机列表

// TODO: 在此添加额外的初始化代码
    DWORD dwNeeded;
    DWORD dwReturn;
    DWORD dwFlag = PRINTER_ENUM_CONNECTIONS | PRINTER_ENUM_LOCAL;

    EnumPrinters(dwFlag, NULL, 4, NULL, 0, &dwNeeded, &dwReturn);

    PRINTER_INFO_4* p4;
    p4 = new PRINTER_INFO_4[dwNeeded];
    EnumPrinters(dwFlag, NULL, 4, (PBYTE)p4, dwNeeded, &dwNeeded, &dwReturn);

    for (int i = 0; i<(int)dwReturn; i++)
        this->m_cboPrint.AddString(p4[i].pPrinterName);

    delete []p4;

3、操作对话框，在IDC_EDIT1里输入打印的内容，在IDC_COMBO1里选中打印机；

4、打印（我是用OK按钮打印的，大家随便）

// TODO: 在此添加控件通知处理程序代码
//  CDialogEx::OnOK();
    this->UpdateData();

    CString strMessage;
    CString strPrintDevice;

    this->GetDlgItem(IDC_EDIT1)->GetWindowTextW(strMessage);
    strMessage += _T("
");       //添加结尾，方便后面循环读取打印数据

    this->GetDlgItem(IDC_COMBO1)->GetWindowTextW(strPrintDevice);

    DWORD dwFlag = PD_ALLPAGES | PD_NOPAGENUMS | PD_USEDEVMODECOPIES | PD_HIDEPRINTTOFILE;  //打印配置界面的按钮可用性，因为后台打印，其实这个配置没什么意义

    CPrintDialog pPrintdlg(FALSE, dwFlag, this);                                            //CPrintDialog实例化，因为MFC的打印设备无关性，可以理解为这就是一台打印机

    HGLOBAL hDevMode = NULL;
    HGLOBAL hDevNames = NULL;
    if (GetPrinterDevice(strPrintDevice.GetBuffer(0), &hDevNames, &hDevMode))               //获得指定打印机的配置、名字
        AfxGetApp()->SelectPrinter(hDevNames, hDevMode);
    else
        AfxMessageBox(_T("Failed to select custom printer"));

    strPrintDevice.ReleaseBuffer();

    pPrintdlg.m_pd.hDevMode = hDevMode;                                                     //让pPrintdlg使用我们指定的打印机
    pPrintdlg.m_pd.hDevNames = hDevNames;

    CDC dc;
    dc.Attach(pPrintdlg.CreatePrinterDC());                                                 //后台打印创建法，如果需要弹出打印对话框，请用DoModal

    DOCINFO di;                                                                             //下面的内容网上很多，就不解释了
    di.cbSize = sizeof(DOCINFO);
    di.lpszDocName = _T("有驱打印测试");
    di.lpszDatatype = NULL;
    di.lpszOutput = NULL;
    di.fwType = 0;

    dc.StartDocW(&di);
    dc.StartPage();
    dc.SetMapMode(MM_TEXT);

    CRect recPrint(0, 0, dc.GetDeviceCaps(LOGPIXELSX), dc.GetDeviceCaps(LOGPIXELSY));
    dc.DPtoLP(&recPrint);
    dc.SetWindowOrg(0, 0);

    CFont newFont;
    VERIFY(newFont.CreatePointFont(120, _T("宋体"), &dc));
    CFont* oldFont = dc.SelectObject(&newFont);

    dc.SetTextAlign(TA_TOP | TA_LEFT);

    CString strPrint;
    int nIndex = 0;
    int x = 50;
    int y = 50;
    CSize textSize;
    textSize = dc.GetTextExtent(_T("00"), 2);                           //根据当前字体的宽、高，后面以此高度为行高

    while ((nIndex = strMessage.Find(_T("
"))) > -1)                  //将IDC_EDIT1编辑框中内容打印，支持换行，一次换行等于'
'，所以在开头strMessage += _T("
")
    {
        strPrint = strMessage.Left(nIndex);
        strMessage = strMessage.Mid(nIndex+2);

        dc.TextOutW(x, y, strPrint);

        y += textSize.cy;                                               //下移一行，行高为字体高度
    }

    dc.SelectObject(oldFont);
    newFont.DeleteObject();
    dc.EndPage();
    dc.EndDoc();
    DeleteDC(dc.Detach());

关于GetPrinterDevice，来自微软的一篇文章，点我跳转

代码也贴出来

BOOL CMFCApplication2Dlg::GetPrinterDevice(LPTSTR pszPrinterName, HGLOBAL* phDevNames, HGLOBAL* phDevMode)
{
    // if NULL is passed, then assume we are setting app object's
    // devmode and devnames
    if (phDevMode == NULL || phDevNames == NULL)
        return FALSE;

    // Open printer
    HANDLE hPrinter;
    if (OpenPrinter(pszPrinterName, &hPrinter, NULL) == FALSE)
        return FALSE;

    // obtain PRINTER_INFO_2 structure and close printer
    DWORD dwBytesReturned, dwBytesNeeded;
    GetPrinter(hPrinter, 2, NULL, 0, &dwBytesNeeded);
    PRINTER_INFO_2* p2 = (PRINTER_INFO_2*)GlobalAlloc(GPTR,
        dwBytesNeeded);
    if (GetPrinter(hPrinter, 2, (LPBYTE)p2, dwBytesNeeded,
        &dwBytesReturned) == 0) {
            GlobalFree(p2);
            ClosePrinter(hPrinter);
            return FALSE;
    }
    ClosePrinter(hPrinter);

    // Allocate a global handle for DEVMODE
    HGLOBAL  hDevMode = GlobalAlloc(GHND, sizeof(*p2->pDevMode) +
        p2->pDevMode->dmDriverExtra);
    ASSERT(hDevMode);
    DEVMODE* pDevMode = (DEVMODE*)GlobalLock(hDevMode);
    ASSERT(pDevMode);

    // copy DEVMODE data from PRINTER_INFO_2::pDevMode
    memcpy(pDevMode, p2->pDevMode, sizeof(*p2->pDevMode) +
        p2->pDevMode->dmDriverExtra);
    GlobalUnlock(hDevMode);

    // Compute size of DEVNAMES structure from PRINTER_INFO_2's data
    DWORD drvNameLen = lstrlen(p2->pDriverName)+1;  // driver name
    DWORD ptrNameLen = lstrlen(p2->pPrinterName)+1; // printer name
    DWORD porNameLen = lstrlen(p2->pPortName)+1;    // port name

    // Allocate a global handle big enough to hold DEVNAMES.
    HGLOBAL hDevNames = GlobalAlloc(GHND,
        sizeof(DEVNAMES) +
        (drvNameLen + ptrNameLen + porNameLen)*sizeof(TCHAR));
    ASSERT(hDevNames);
    DEVNAMES* pDevNames = (DEVNAMES*)GlobalLock(hDevNames);
    ASSERT(pDevNames);

    // Copy the DEVNAMES information from PRINTER_INFO_2
    // tcOffset = TCHAR Offset into structure
    int tcOffset = sizeof(DEVNAMES)/sizeof(TCHAR);
    ASSERT(sizeof(DEVNAMES) == tcOffset*sizeof(TCHAR));

    pDevNames->wDriverOffset = tcOffset;
    memcpy((LPTSTR)pDevNames + tcOffset, p2->pDriverName,
        drvNameLen*sizeof(TCHAR));
    tcOffset += drvNameLen;

    pDevNames->wDeviceOffset = tcOffset;
    memcpy((LPTSTR)pDevNames + tcOffset, p2->pPrinterName,
        ptrNameLen*sizeof(TCHAR));
    tcOffset += ptrNameLen;

    pDevNames->wOutputOffset = tcOffset;
    memcpy((LPTSTR)pDevNames + tcOffset, p2->pPortName,
        porNameLen*sizeof(TCHAR));
    pDevNames->wDefault = 0;

    GlobalUnlock(hDevNames);
    GlobalFree(p2);   // free PRINTER_INFO_2

    // set the new hDevMode and hDevNames
    *phDevMode = hDevMode;
    *phDevNames = hDevNames;
    return TRUE;
}

基本上是完整代码了，如果有内存错误，请联系我