UTF8的编码解码

喜欢ヅ旅行 2022-09-18 13:56 241阅读 0赞

#include "stdafx.h"
    #include <string>
    #include <clocale>
    using namespace std;
    
    #include "charsetCvt.h"
    string ws2s(const wstring& ws)
    {
    	string curLocale = setlocale(LC_ALL, NULL); // curLocale = "C";
    	setlocale(LC_ALL, "chs"); 
    	const wchar_t* _Source = ws.c_str();
    	size_t _Dsize = 2 * ws.size() + 1;
    	char *_Dest = new char[_Dsize];
    	memset(_Dest,0,_Dsize);
    	wcstombs(_Dest,_Source,_Dsize);
    	string result = _Dest;
    	delete []_Dest;
    	setlocale(LC_ALL, curLocale.c_str());
    	return result;
    }
     
    
    wstring s2ws(const string& s)
    {
    	setlocale(LC_ALL, "chs"); 
    	const char* _Source = s.c_str();
    	size_t _Dsize = s.size() + 1;
    	wchar_t *_Dest = new wchar_t[_Dsize];
    	wmemset(_Dest, 0, _Dsize);
    	int nret = mbstowcs(_Dest,_Source,_Dsize);
    	wstring result = _Dest;
    	delete []_Dest;
    	setlocale(LC_ALL, "C");
     
    	return result;
    
    }
    
    
     
    wstring UTF2Uni(const char* src, std::wstring &t)
    {
    	if (src == NULL) 
    	{
    		return L"";
    	}
    	
    	int size_s = strlen(src);
    	int size_d = size_s + 10;          //?
    	
    	wchar_t *des = new wchar_t[size_d];
    	memset(des, 0, size_d * sizeof(wchar_t));
    	
    	int s = 0, d = 0;
    	bool toomuchbyte = true; //set true to skip error prefix.
    	
    	while (s < size_s && d < size_d)
    	{
    		unsigned char c = src[s];
    		if ((c & 0x80) == 0) 
    		{
    			des[d++] += src[s++];
    		} 
    		else if((c & 0xE0) == 0xC0)  ///< 110x-xxxx 10xx-xxxx
    		{
    			WCHAR &wideChar = des[d++];
    			wideChar  = (src[s + 0] & 0x3F) << 6;
    			wideChar |= (src[s + 1] & 0x3F);
    			
    			s += 2;
    		}
    		else if((c & 0xF0) == 0xE0)  ///< 1110-xxxx 10xx-xxxx 10xx-xxxx
    		{
    			WCHAR &wideChar = des[d++];
    			
    			wideChar  = (src[s + 0] & 0x1F) << 12;
    			wideChar |= (src[s + 1] & 0x3F) << 6;
    			wideChar |= (src[s + 2] & 0x3F);
    			
    			s += 3;
    		} 
    		else if((c & 0xF8) == 0xF0)  ///< 1111-0xxx 10xx-xxxx 10xx-xxxx 10xx-xxxx 
    		{
    			WCHAR &wideChar = des[d++];
    			
    			wideChar  = (src[s + 0] & 0x0F) << 18;
    			wideChar  = (src[s + 1] & 0x3F) << 12;
    			wideChar |= (src[s + 2] & 0x3F) << 6;
    			wideChar |= (src[s + 3] & 0x3F);
    			
    			s += 4;
    		} 
    		else 
    		{
    			WCHAR &wideChar = des[d++]; ///< 1111-10xx 10xx-xxxx 10xx-xxxx 10xx-xxxx 10xx-xxxx 
    			
    			wideChar  = (src[s + 0] & 0x07) << 24;
    			wideChar  = (src[s + 1] & 0x3F) << 18;
    			wideChar  = (src[s + 2] & 0x3F) << 12;
    			wideChar |= (src[s + 3] & 0x3F) << 6;
    			wideChar |= (src[s + 4] & 0x3F);
    			
    			s += 5;
    		}
    	}
    	
    	t = des;
    	delete[] des;
    	des = NULL;
    	
    	return t;
    }
    
    
    
    int Uni2UTF( const wstring& strRes, char *utf8, int nMaxSize )
    {
    	if (utf8 == NULL) {
    		return -1;
    	}
    	int len = 0;
    	int size_d = nMaxSize;
    
    
    	for (wstring::const_iterator it = strRes.begin(); it != strRes.end(); ++it)
    	{
    		wchar_t wchar = *it;
    		if (wchar < 0x80)
    		{  //
    			//length = 1;
    			utf8[len++] = (char)wchar;
    		}
    		else if(wchar < 0x800)
    		{
    			//length = 2;
    			
    			if (len + 1 >= size_d)
    				return -1;
    			
    			utf8[len++] = 0xc0 | ( wchar >> 6 );
    			utf8[len++] = 0x80 | ( wchar & 0x3f );
    		}
    		else if(wchar < 0x10000 )
    		{
    			//length = 3;
    			if (len + 2 >= size_d)
    				return -1;
    			
    			utf8[len++] = 0xe0 | ( wchar >> 12 );
    			utf8[len++] = 0x80 | ( (wchar >> 6) & 0x3f );
    			utf8[len++] = 0x80 | ( wchar & 0x3f );
    		}
    		else if( wchar < 0x200000 ) 
    		{
    			//length = 4;
    			if (len + 3 >= size_d)
    				return -1;
    			
    			utf8[len++] = 0xf0 | ( (int)wchar >> 18 );
    			utf8[len++] = 0x80 | ( (wchar >> 12) & 0x3f );
    			utf8[len++] = 0x80 | ( (wchar >> 6) & 0x3f );
    			utf8[len++] = 0x80 | ( wchar & 0x3f );
    		}
    	
    	}
    	
    
    	return len;
    }
    
    string s2utfs(const  string&  strSrc)
    {
    	string  strRes;
    	wstring  wstrUni = s2ws(strSrc);
    	
    	char*  chUTF8 = new char[wstrUni.length() * 3];
    	memset(chUTF8,0x00,wstrUni.length() * 3);
    	Uni2UTF(wstrUni,chUTF8, wstrUni.length() * 3);
    	strRes = chUTF8;	
    	delete  []chUTF8;
    	return strRes;
    }
    
    
    string  utfs2s(const string& strutf)
    {
    	wstring  wStrTmp;
    	UTF2Uni( strutf.c_str(),wStrTmp);
    	return ws2s(wStrTmp);
    }

转帖：http://bbs.csdn.net/topics/320095332\#post-321018425