VC中精确获取字符串长宽

void CTestDlg::OnButton1()
{
     // TODO: Add your control notification handler code here
     CDC* pDC;
    
     LOGFONT tLogFont;
     tLogFont.lfHeight = 21;
     tLogFont.lfWidth  = 0;
     tLogFont.lfEscapement = 0;
     tLogFont.lfOrientation = 0;
     tLogFont.lfWeight = FW_NORMAL;
     tLogFont.lfItalic = 1;
     tLogFont.lfUnderline = 0;
     tLogFont.lfStrikeOut = 0;
     tLogFont.lfCharSet = GB2312_CHARSET;
     tLogFont.lfOutPrecision = OUT_DEFAULT_PRECIS;
     tLogFont.lfClipPrecision = CLIP_DEFAULT_PRECIS;
     tLogFont.lfQuality = DEFAULT_QUALITY;
     tLogFont.lfPitchAndFamily = DEFAULT_PITCH | FF_SWISS;
     strcpy( tLogFont.lfFaceName, _T("宋体") );
 
    
     RECT rect;
     CFont rFont;
     CFont* pOldFont;
     rect.left = 10;
     rect.right = 10;
     rect.top = 10;
     rect.bottom = 10;
 
     pDC = GetDC( );
     rFont.CreateFontIndirect( &tLogFont );
     pOldFont = pDC->SelectObject( &rFont );
 
     //测试字符串
     CString sTestStr = "asdfas基本面有dasdf在在有有dffds有有有有有有sdfasdfa城  在 sdf~!@#$%^&*()_+sdfasdfasdf";
     //此处nHeight为字符串高度,rect为测试后字符串显示所站区域大小
     int nHeight = pDC->DrawText( sTestStr,&rect, DT_SINGLELINE|DT_LEFT| DT_CALCRECT);
     pDC->DrawText( sTestStr,&rect, DT_SINGLELINE|DT_LEFT);
     //在区域最后画一条竖线来测试结果
     pDC->MoveTo( rect.right, rect.top );
     pDC->LineTo( rect.right, rect.bottom );
     //释放资源
     pDC->SelectObject( pOldFont );
     rFont.DeleteObject( );
     ReleaseDC( pDC );
}