void CTest1Dlg::OnButton4()
{
 // TODO: Add your control notification handler code here
 TEXTMETRIC tm;
 CDC* pDC = GetDC();
 pDC->GetTextMetrics(&tm);

 LONG ltmheight = tm.tmHeight;

 CString str;
 str.Format("当前DC结构中的字体大小%i",ltmheight);
 AfxMessageBox(str);

 this->ReleaseDC(pDC); 
}