aspect ratio of image crashing the program

问题:

here is the code this code is to maintain the aspect ratio of the image it crashes when the control goes to int WindowRatio = WidthOfPreviewPane / HeightOfPreviewPane; can anyone give idea why ??

int WidthOfPreviewPane = RECTWIDTH(m_rcParent); 
int HeightOfPreviewPane = RECTHEIGHT(m_rcParent) ; 

int ImageRatio = WidthOfImage / HeightOfImage;
int WindowRatio = WidthOfPreviewPane / HeightOfPreviewPane;

if (WindowRatio > ImageRatio && WidthOfPreviewPane< WidthOfImage)
{
    m_iFinalHeight = HeightOfPreviewPane;
    m_iFinalWidth = m_iFinalHeight * ImageRatio;
    MessageBox(NULL, L"1",L"Error", 
            MB_ICONERROR | MB_OK);
}
else if (WindowRatio < ImageRatio && WidthOfPreviewPane< WidthOfImage)
{
    m_iFinalWidth = WidthOfPreviewPane;
    m_iFinalHeight = m_iFinalWidth / ImageRatio;
        MessageBox(NULL, L"2",L"Error", 
            MB_ICONERROR | MB_OK);
}
else if(WindowRatio > ImageRatio && WidthOfPreviewPane> WidthOfImage)
{
    m_iFinalHeight = HeightOfImage;
    m_iFinalWidth = WidthOfImage;
        MessageBox(NULL, L"3",L"Error", 
            MB_ICONERROR | MB_OK);

}
else if(WindowRatio < ImageRatio && WidthOfPreviewPane> WidthOfImage)
{
    m_iFinalHeight = HeightOfImage;
    m_iFinalWidth = WidthOfImage;
        MessageBox(NULL, L"4",L"Error", 
            MB_ICONERROR | MB_OK);

}

回答1:

the logic of this algo is correct finally i found that WidthOfPreviewPane and HeightOfPreviewPane=0 its because the function in which i have written this code was initialized at last so these 2 were not initialized that time when i debugged them and i avoided thid problem by putting them in in a if condition which will let the control go inside if their value is not 0 and it worked nicely. see this-

 if(WidthOfPreviewPane!= 0 && HeightOfPreviewPane!=0 )
            {
                  conditions here......

            }

and thats solved.