MFC 根据字符宽度居中

Gdiplus::Font font(_T("微软雅黑"), (Gdiplus::REAL)130);
Gdiplus::RectF orgin(0.0f, 100.0f, nWidth, 200.0f);
Gdiplus::StringFormat stringformat;
stringformat.SetAlignment(Gdiplus::StringAlignmentCenter);
//stringformat.SetLineAlignment(Gdiplus::StringAlignmentCenter);
Gdiplus::SolidBrush solidBrush(Gdiplus::Color(255, 255, 0, 0));
graphics.DrawString(strFailedContent.c_str(), -1, &font, orgin, &stringformat, &solidBrush);

float GetTextWidthFloor(const wstring& strText, const Gdiplus::Font& font)
{
Gdiplus::StringFormat stringformat(Gdiplus::StringAlignmentNear);Gdiplus::GraphicsPath graphicsPathObj;
Gdiplus::FontFamily fontfamily;
font.GetFamily(&fontfamily);Gdiplus::RectF rcBound;
graphicsPathObj.AddString(strText.c_str(), -1, &fontfamily, font.GetStyle(), font.GetSize(), Gdiplus::PointF(0, 0), &stringformat);
graphicsPathObj.GetBounds(&rcBound);return (float)(rcBound.Width);
}int GetTextWidth(const wstring& strText, const Gdiplus::Font& font)
{
// calculate spaces width of text head
// due to gdiplus do not care about it
int nHeadSpace = 0;
int nLen = strText.size();
for (int i=0; i<nLen; ++i)
{
if (0x20 == strText.at(i))
nHeadSpace++;
else{
break;
}
}// calculate space width
static float fSpaceWidth = 0.0f;
if ((fSpaceWidth >= -0.00001f && fSpaceWidth <= 0.00001f) && nHeadSpace > 0)
{
fSpaceWidth = GetTextWidthFloor(_T("a b"), font) - GetTextWidthFloor(_T("ab"), font);
}float fResult = GetTextWidthFloor(strText, font) + (float)nHeadSpace * fSpaceWidth;return (int)fResult + 1;
}