宽字符和窄字符的转换接口

作者：朱金灿

来源：http://blog.csdn.net/clever101

 

     宽字符和窄字符的转换需求很经常会遇到，今天从网上找了两个函数，修改了一下，奉献给大家。

#include <string>
#include <assert.h>

std::wstring toWideString( const char* pStr,int len)
{
	assert(pStr) ; 
	assert(len >= 0 || len == -1, _T("Invalid string length: ") << len ) ;

	// figure out how many wide characters we are going to get 
	int nChars = MultiByteToWideChar( CP_ACP , 0 , pStr , len , NULL , 0 ) ; 
	if ( len == -1 )
		-- nChars ; 
	if ( nChars == 0 )
		return L"" ;

	// convert the narrow string to a wide string 
	// nb: slightly naughty to write directly into the string like this
	std::wstring buf;
	buf.resize(nChars); 
	::MultiByteToWideChar(CP_ACP,0,pStr,len,const_cast<wchar_t*>(buf.c_str()),nChars); 

	return buf ;
}

std::wstring toWideString(const std::string& strA)
{
	const char* pStr = strA.c_str();
	int len = strA.length();
    return toWideString(pStr,len);
}

std::string toNarrowString( const wchar_t* pStr,int len)
{    
	// figure out how many narrow characters we are going to get 
	assert(pStr) ; 
	assert(len >= 0 || len == -1 , _T("Invalid string length: ") << len ) ; 

	int nChars = WideCharToMultiByte( CP_ACP , 0 , 
		pStr , len , NULL , 0 , NULL , NULL ) ; 
	if ( len == -1 )
		-- nChars ; 
	if ( nChars == 0 )
		return "" ;

	// convert the wide string to a narrow string
	// nb: slightly naughty to write directly into the string like this
	std::string buf ;
	buf.resize(nChars);
	WideCharToMultiByte(CP_ACP,0,pStr,len,const_cast<char*>(buf.c_str()),nChars,NULL,NULL); 

	return buf ; 
}

std::string toNarrowString(const std::wstring& strW)
{
	const wchar_t* pStr = strW.c_str();
	int len = strW.length();
    return toNarrowString(pStr,len);
}

      有问题或者更好意见的话请联系我。

 

参考文献：

 

1. 如何升级基于STL的应用来支持Unicode