宽字符和窄字符的转换接口

转载

mob604756f4c9c3 2012-08-16 18:45:00

文章标签 ide #include 参考文献宽字符 ico 文章分类 代码人生

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);
}