在项目开发过程中,经常会使用到c++ 的url编码和解码,本文将以此问题详细介绍使用技巧,需要的朋友可以参考下
 
#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); 
}; 
  
#include "StdAfx.h" 
#include "./urlcodeing.h" 
//这是个类strCoding (strCoding.cpp文件) 
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gb2312 
 
void 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-8 
 
void 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%88 
 
string 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%88 
 
string 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; 
}