宽字符和窄字符的转换接口

作者：朱金灿

来源：http://blog.csdn.net/clever101/article/details/7874595

     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);  }

参考文献：

 

1. 如何升级基于STL的应用来支持Unicode