如何防止粘贴的图像溢出其边界？

Question

我将图像插入Excel范围内，如下所示：

    private System.Drawing.Image _logo;

    public ProduceUsageRpt(..., System.Drawing.Image logo)
    {
        . . .
        _logo = logo;
    }
    . . .
    var logoRange = _xlSheet.Range[
    _xlSheet.Cells[LOGO_FIRST_ROW, _grandTotalsColumn], _xlSheet.Cells[LOGO_LAST_ROW, _grandTotalsColumn]];
Clipboard.SetDataObject(_logo, true);
_xlSheet.Paste(logoRange, _logo);

不幸的是，该图像对于该范围太大（当前为第1行到第4行，第16列）。 它没有做礼貌的事情并按比例缩小以适应规定的范围，而是溢出并超出了它指定的垂直和水平位置。

如何获得按比例缩小的图像并将其限制在其“框”内？

Answer 1

我从这里的一个相关问题改编得到了答案。

只要我使范围足够大，它就可以工作：

    . . .
    var logoRange = _xlSheet.Range[
        _xlSheet.Cells[LOGO_FIRST_ROW, _grandTotalsColumn], _xlSheet.Cells[LOGO_LAST_ROW, _grandTotalsColumn+1]];
    PlacePicture(_logo, logoRange);
}

// From Jürgen Tschandl
private void PlacePicture(Image picture, Range destination)
{
    Worksheet ws = destination.Worksheet;
    Clipboard.SetImage(picture);
    ws.Paste(destination, false);
    Pictures p = ws.Pictures(System.Reflection.Missing.Value) as Pictures;
    Picture pic = p.Item(p.Count) as Picture;
    ScalePicture(pic, (double)destination.Width, (double)destination.Height);
}

// Also from Jürgen Tschandl
private void ScalePicture(Picture pic, double width, double height)
{
    double fX = width / pic.Width;
    double fY = height / pic.Height;
    double oldH = pic.Height;
    if (fX < fY)
    {
        pic.Width *= fX;
        if (pic.Height == oldH) // no change if aspect ratio is locked
            pic.Height *= fX;
        pic.Top += (height - pic.Height) / 2;
    }
    else
    {
        pic.Width *= fY;
        if (pic.Height == oldH) // no change if aspect ratio is locked
            pic.Height *= fY;
        pic.Left += (width - pic.Width) / 2;
    }
}