// CImageProcessingView

IMPLEMENT_DYNCREATE(CImageProcessingView, CScrollView)

BEGIN_MESSAGE_MAP(CImageProcessingView, CScrollView)
    //{{AFX_MSG_MAP(CImageProcessingView)
    ON_COMMAND(ID_EDGE_CANNY, OnEdgeCanny)
    //}}AFX_MSG_MAP
    // Standard printing commands
    ON_COMMAND(ID_FILE_PRINT, CScrollView::OnFilePrint)
    ON_COMMAND(ID_FILE_PRINT_DIRECT, CScrollView::OnFilePrint)
    ON_COMMAND(ID_FILE_PRINT_PREVIEW, CScrollView::OnFilePrintPreview)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
error C2065: 'ID_EDGE_CANNY' : undeclared identifier
执行 cl.exe 时出错.

看上去象是侧边框控件,明确一下,然后到资源管理窗口里找找它的ID是不是改了而这里没有改.