C/C++ 字符编码的转换(ut8、gb2312)

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//这是个类strCoding (strCoding.h文件)#pragma once#include <iostream>#include <string>#include <windows.h>using namespace std;class strCoding{public:    strCoding(void);    ~strCoding(void);       void UTF_8ToGB2312(string &pOut, char *pText, int pLen);//utf_8转为gb2312    void GB2312ToUTF_8(string& pOut,char *pText, int pLen); //gb2312 转utf_8    string UrlGB2312(char * str);                           //urlgb2312编码    string UrlUTF8(char * str);                             //urlutf8 编码    string UrlUTF8Decode(string str);                  //urlutf8解码    string UrlGB2312Decode(string str);                //urlgb2312解码  private:    void Gb2312ToUnicode(WCHAR* pOut,char *gbBuffer);    void UTF_8ToUnicode(WCHAR* pOut,char *pText);    void UnicodeToUTF_8(char* pOut,WCHAR* pText);    void UnicodeToGB2312(char* pOut,WCHAR uData);    char  CharToInt(char ch);    char StrToBin(char *str);}; //这是个类strCoding (strCoding.cpp文件)#include "StdAfx.h"#include ".\strcoding.h"strCoding::strCoding(void){}strCoding::~strCoding(void){}void strCoding::Gb2312ToUnicode(WCHAR* pOut,char *gbBuffer){    ::MultiByteToWideChar(CP_ACP,MB_PRECOMPOSED,gbBuffer,2,pOut,1);    return;}void strCoding::UTF_8ToUnicode(WCHAR* pOut,char *pText){    char* uchar = (char *)pOut;         uchar[1] = ((pText[0] & 0x0F) << 4) + ((pText[1] >> 2) & 0x0F);    uchar[0] = ((pText[1] & 0x03) << 6) + (pText[2] & 0x3F);    return;}void strCoding::UnicodeToUTF_8(char* pOut,WCHAR* pText){    // 注意 WCHAR高低字的顺序,低字节在前，高字节在后    char* pchar = (char *)pText;    pOut[0] = (0xE0 | ((pchar[1] & 0xF0) >> 4));    pOut[1] = (0x80 | ((pchar[1] & 0x0F) << 2)) + ((pchar[0] & 0xC0) >> 6);    pOut[2] = (0x80 | (pchar[0] & 0x3F));    return;}void strCoding::UnicodeToGB2312(char* pOut,WCHAR uData){    WideCharToMultiByte(CP_ACP,NULL,&uData,1,pOut,sizeof(WCHAR),NULL,NULL);    return;}//做为解Url使用char strCoding:: CharToInt(char ch){        if(ch>='0' && ch<='9')return (char)(ch-'0');        if(ch>='a' && ch<='f')return (char)(ch-'a'+10);        if(ch>='A' && ch<='F')return (char)(ch-'A'+10);        return -1;}char strCoding::StrToBin(char *str){        char tempWord[2];        char chn;        tempWord[0] = CharToInt(str[0]);                         //make the B to 11 -- 00001011        tempWord[1] = CharToInt(str[1]);                         //make the 0 to 0  -- 00000000        chn = (tempWord[0] << 4) | tempWord[1];                //to change the BO to 10110000        return chn;}//UTF_8 转gb2312void strCoding::UTF_8ToGB2312(string &pOut, char *pText, int pLen){     char buf[4];     char* rst = new char[pLen + (pLen >> 2) + 2];    memset(buf,0,4);    memset(rst,0,pLen + (pLen >> 2) + 2);    int i =0;    int j = 0;          while(i < pLen)    {        if(*(pText + i) >= 0)        {                        rst[j++] = pText[i++];        }        else                         {            WCHAR Wtemp;                        UTF_8ToUnicode(&Wtemp,pText + i);                          UnicodeToGB2312(buf,Wtemp);                        unsigned short int tmp = 0;            tmp = rst[j] = buf[0];            tmp = rst[j+1] = buf[1];            tmp = rst[j+2] = buf[2];            //newBuf[j] = Ctemp[0];            //newBuf[j + 1] = Ctemp[1];            i += 3;                j += 2;           }          }    rst[j]='\0';   pOut = rst;     delete []rst;}//GB2312 转为 UTF-8void strCoding::GB2312ToUTF_8(string& pOut,char *pText, int pLen){    char buf[4];    memset(buf,0,4);    pOut.clear();    int i = 0;    while(i < pLen)    {        //如果是英文直接复制就可以        if( pText[i] >= 0)        {            char asciistr[2]={0};            asciistr[0] = (pText[i++]);            pOut.append(asciistr);        }        else        {            WCHAR pbuffer;            Gb2312ToUnicode(&pbuffer,pText+i);            UnicodeToUTF_8(buf,&pbuffer);            pOut.append(buf);            i += 2;        }    }    return;}//把str编码为网页中的 GB2312 url encode ,英文不变，汉字双字节  如%3D%AE%88string strCoding::UrlGB2312(char * str){    string dd;    size_t len = strlen(str);    for (size_t i=0;i<len;i++)    {        if(isalnum((BYTE)str[i]))        {            char tempbuff[2];            sprintf(tempbuff,"%c",str[i]);            dd.append(tempbuff);        }        else if (isspace((BYTE)str[i]))        {            dd.append("+");        }        else        {            char tempbuff[4];            sprintf(tempbuff,"%%%X%X",((BYTE*)str)[i] >>4,((BYTE*)str)[i] %16);            dd.append(tempbuff);        }    }    return dd;}//把str编码为网页中的 UTF-8 url encode ,英文不变，汉字三字节  如%3D%AE%88string strCoding::UrlUTF8(char * str){    string tt;    string dd;    GB2312ToUTF_8(tt,str,(int)strlen(str));    size_t len=tt.length();    for (size_t i=0;i<len;i++)    {        if(isalnum((BYTE)tt.at(i)))        {            char tempbuff[2]={0};            sprintf(tempbuff,"%c",(BYTE)tt.at(i));            dd.append(tempbuff);        }        else if (isspace((BYTE)tt.at(i)))        {            dd.append("+");        }        else        {            char tempbuff[4];            sprintf(tempbuff,"%%%X%X",((BYTE)tt.at(i)) >>4,((BYTE)tt.at(i)) %16);            dd.append(tempbuff);        }    }    return dd;}//把url GB2312解码string strCoding::UrlGB2312Decode(string str){   string output="";        char tmp[2];        int i=0,idx=0,ndx,len=str.length();                while(i<len){                if(str[i]=='%'){                        tmp[0]=str[i+1];                        tmp[1]=str[i+2];                        output += StrToBin(tmp);                        i=i+3;                }                else if(str[i]=='+'){                        output+=' ';                        i++;                }                else{                        output+=str[i];                        i++;                }        }                return output;}//把url utf8解码string strCoding::UrlUTF8Decode(string str){     string output="";    string temp =UrlGB2312Decode(str);//    UTF_8ToGB2312(output,(char *)temp.data(),strlen(temp.data()));    return output;}//test#include "stdafx.h"#include "strCoding.h"using namespace std;int main(){          strCoding cfm;     string keyword="大家好,欢迎你";     string Temp="";     string Output="";     //把关键字做url的utf8编码     Temp= cfm.UrlUTF8((char *)keyword.data());     cout<<Temp<<endl;         //把url的utf8编码的结果解码     Temp =cfm.UrlUTF8Decode(Temp);     cout<<Temp<<endl;     //把关键字做url的gb2312编码     Temp =cfm.UrlGB2312((char *)keyword.data());     cout<<Temp<<endl;          //把url的gb2312编码的结果解码     Temp =cfm.UrlGB2312Decode(Temp);     cout<<Temp<<endl;     //把关键字GB2312转UTF_8         cfm.GB2312ToUTF_8(Output,(char *)keyword.data(),strlen(keyword.data()));     cout<<Output<<endl;     //把GB2312转UTF_8转为中文     cfm.UTF_8ToGB2312(Temp,(char *)Output.data(),strlen(Output.data()));     cout<<Temp<<endl;    //system("pasue");     getchar();    return 0;    //}