打印时调试断言错误

Posted 2023-02-16

【中文标题】打印时调试断言错误

【英文标题】：Debug assertion error on printing

【发布时间】：2014-03-26 00:04:30

【问题描述】：

我有一个在 Visual Studio 2010 专业版中创建的简单文本编辑器。基本上我修改了VS2010向导自动生成的MFC MDI程序。问题是当我打印时，它在 viewrich.cpp 第 294 行给了我一个调试断言错误。我没有修改代码中与打印有关的任何内容，尽管我使用 Rich Edit 的方式可能有问题。这就是我掌握的所有信息。提前致谢。

Viewrich.cpp

BOOL CRichEditView::PaginateTo(CDC* pDC, CPrintInfo* pInfo)
// attempts pagination to pInfo->m_nCurPage, TRUE == success

ASSERT_VALID(this);
ASSERT_VALID(pDC);

CRect rectSave = pInfo->m_rectDraw;
UINT nPageSave = pInfo->m_nCurPage;
ASSERT(nPageSave > 1); // LINE 294
ASSERT(nPageSave >= (UINT)m_aPageStart.GetSize());
VERIFY(pDC->SaveDC() != 0);
pDC->IntersectClipRect(0, 0, 0, 0);
pInfo->m_nCurPage = (int)m_aPageStart.GetSize();
while (pInfo->m_nCurPage < nPageSave)

    ASSERT(pInfo->m_nCurPage == (UINT)m_aPageStart.GetSize());
    OnPrepareDC(pDC, pInfo);
    ASSERT(pInfo->m_bContinuePrinting);
    pInfo->m_rectDraw.SetRect(0, 0,
        pDC->GetDeviceCaps(HORZRES), pDC->GetDeviceCaps(VERTRES));
    pDC->DPtoLP(&pInfo->m_rectDraw);
    OnPrint(pDC, pInfo);
    if (pInfo->m_nCurPage == (UINT)m_aPageStart.GetSize())
        break;
    ++pInfo->m_nCurPage;

BOOL bResult = pInfo->m_nCurPage == nPageSave;
pDC->RestoreDC(-1);
pInfo->m_nCurPage = nPageSave;
pInfo->m_rectDraw = rectSave;
ASSERT_VALID(this);
return bResult;

EmergenceView.cpp

IMPLEMENT_DYNCREATE(CEmergenceView, CRichEditView)

BEGIN_MESSAGE_MAP(CEmergenceView, CRichEditView)
// Standard printing commands
ON_COMMAND(ID_FILE_PRINT, &CRichEditView::OnFilePrint)
ON_COMMAND(ID_FILE_PRINT_DIRECT, &CRichEditView::OnFilePrint)
ON_COMMAND(ID_FILE_PRINT_PREVIEW, &CEmergenceView::OnFilePrintPreview)
ON_WM_CONTEXTMENU()
ON_WM_RBUTTONUP()
ON_COMMAND(ID_MUTATE_GROUP, &CEmergenceView::OnMutateGroup)
ON_UPDATE_COMMAND_UI(ID_MUTATE_GROUP, &CEmergenceView::OnUpdateMutateGroup)
ON_COMMAND(ID_MUTATE_RANDOMISE, &CEmergenceView::OnMutateRandomise)
ON_UPDATE_COMMAND_UI(ID_MUTATE_RANDOMISE, &CEmergenceView::OnUpdateMutateRandomise)
ON_COMMAND(ID_HELP_STATISTICS, &CEmergenceView::OnHelpStatistics)
ON_UPDATE_COMMAND_UI(ID_HELP_STATISTICS, &CEmergenceView::OnUpdateHelpStatistics)
ON_COMMAND(ID_MUTATE_POETRIZE, &CEmergenceView::OnMutatePoetrize)
ON_COMMAND(ID_EDIT_SELECTALL, &CEmergenceView::OnEditSelectall)
END_MESSAGE_MAP()

// CEmergenceView construction/destruction

CEmergenceView::CEmergenceView()

// TODO: add construction code here



CEmergenceView::~CEmergenceView()



BOOL CEmergenceView::PreCreateWindow(CREATESTRUCT& cs)

// TODO: Modify the Window class or styles here by modifying
//  the CREATESTRUCT cs

return CRichEditView::PreCreateWindow(cs);


// CEmergenceView drawing

void CEmergenceView::OnDraw(CDC* /*pDC*/)

CEmergenceDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
if (!pDoc)
    return;

// TODO: add draw code for native data here



// CEmergenceView printing


void CEmergenceView::OnFilePrintPreview()

    #ifndef SHARED_HANDLERS
AFXPrintPreview(this);
    #endif


BOOL CEmergenceView::OnPreparePrinting(CPrintInfo* pInfo)

// default preparation
return DoPreparePrinting(pInfo);


void CEmergenceView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)

// TODO: add extra initialization before printing


void CEmergenceView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)

// TODO: add cleanup after printing

【问题讨论】：

您能否发布断言的 MFC 代码以及启动打印的代码

查看OnPreparePrinting (msdn.microsoft.com/en-us/library/a59dff1e.aspx) 的文档，看来您必须致电pInfo->SetMaxPage()。

【参考方案1】：

断言说明了一切：

UINT nPageSave = pInfo->m_nCurPage;
ASSERT(nPageSave > 1);

这是要打印/分页的当前页面的值。它在 CPrintInfo 的构造函数中设置为 1。但是有些东西改变了它，使它成为 0 或负数。通常这个值完全由 RTF 打印输出控制。所以你必须做一些操纵它的事情。

您必须在 CPrintInfo 中设置最小页面和最大页面值（SetMinPage 和 SetMaxPage）。

【讨论】：

我已经设置了最小页面和最大页面，但它仍然给我同样的错误......