duilib获取字符串的像素长

		CDuiString m_test_string = _T("测试字符串")
		HDC m_hDc = m_pm.GetPaintDC();
		// 100 是xml中配置的字体的编号
		HFONT hFont = m_pm.GetFont(100);
		::SelectObject(m_hDc, hFont);
		SIZE size;
		GetTextExtentPoint32(m_hDc, m_test_string, i, &size);
		return size.cx

The GetTextExtentPoint32 function computes the width and height of the specified string of text.