VC中GetTextMetrics和GetTextExtent用法区别

环境：Visual C++ 6.0

问题：GetTextMetrics和GetTextExtent用法区别

解决：

先来看看MSDN里对它们的解释：

GetTextMetrics：

CDC::GetTextMetrics

BOOLGetTextMetrics( LPTEXTMETRIC lpMetrics) const;

Return Value

Nonzeroif the function is successful; otherwise 0.

Parameters

lpMetrics

Pointsto the TEXTMETRIC structure thatreceives the metrics.

Remarks

Retrievesthe metrics for the current font using the attribute device context.

GetTextExtent：

CDC::GetTextExtent

CSizeGetTextExtent( LPCTSTR lpszString, intnCount) const;

CSizeGetTextExtent( const CString& str ) const;

Return Value

Thedimensions of the string (in logical units) in a CSizeobject.

Parameters

lpszString

Pointsto a string of characters. You can also pass a CStringobject for this parameter.

nCount

Specifiesthe number of characters in the string.

str

ACStringobject that contains the specified characters.

Remarks

Callthis member function to compute the width and height of a line of text usingthe current font to determine the dimensions. The information is retrieved from m_hAttribDC, the attribute devicecontext.

Thecurrent clipping region does not affect the width and height returned by GetTextExtent.

Sincesome devices do not place characters in regular cell arrays (that is, theycarry out kerning), the sum of the extents of the characters in a string maynot be equal to the extent of the string.

 

总结：

1. 本身字体的高度：GetTextMetrics；

2. 求取屏幕上字符串显示的宽度和高度：用GetTextExtent。