C++字符串处理

标题：常见字符串处理代码示例

测试环境：boost 1.55、boost 1.57

注意：部份代码依赖Windows API

[1]删除指定前后缀的字符

#include <boost/algorithm/string.hpp>

...

boost::trim_if(vecRec[0], boost::is_any_of("\" \n\r\t'"));

[2]分割字符串

#include <boost/algorithm/string/split.hpp>

std::vector<std::string> vecRec;
boost::split(vecRec, vecDst[i], boost::is_any_of(":"));

[3]字符替换

x字符替换为y。

std::replace( s.begin(), s.end(), 'x', 'y'); 

头文件

#pragma once#include <string>#include <vector>#include <map>namespace StringHelper{void SplitStr(const std::string& s, std::string& delim,std::vector<std::string> &ret);  void Str2Map(const std::string strSrc, std::map<std::string, std::string> &mapKeyValue);std::string UTF8ToGBK(const std::string &unicode);std::string GBKToUTF8(const std::string& gbk);std::wstring s2ws_UTF8ToGBK(std::string sUTF8);std::wstring s2ws_gbk(const std::string& s);std::string ws2s_gbk(const std::wstring& s);void  string_replace( std::wstring &strBig, const std::wstring &strsrc, const std::wstring &strdst );std::string encodeURI(std::string strSrc);std::string delHeapMemory(char *p);};

实现文件

#include "StringHelper.h"#include <Windows.h>#include <algorithm>  #include <boost/regex.hpp>  #include <boost/algorithm/string.hpp>  #include <locale>#include <codecvt>#include <sstream>using namespace std;/*VC++ 2008 SP1提供了个编译选项，可以默认就构造出UTF8的string。#pragma execution_character_set("utf-8") 另外C++11定义了u8，类似Lstd::string nstr = u8"123,我是谁？";但VS2010SP1并不支持。*/namespace StringHelper{void SplitStr(const std::string& s, std::string& delim,std::vector<std::string> &ret){  size_t last = 0;size_t index=s.find_first_of(delim,last);while (index!=std::string::npos){ret.push_back(s.substr(last,index-last));last=index+1;index=s.find_first_of(delim,last);if (index-last>0){ret.push_back(s.substr(last,index-last));}}}//end funcvoid Str2Map( const std::string strSrc, std::map<std::string, std::string> &mapKeyValue ){ std::vector<std::string> line;  boost::split(line, strSrc, boost::is_any_of(";"));  for (unsigned int i = 0; i < line.size(); i++)  {  std::vector<std::string> vecT;  boost::split(vecT, line[i], boost::is_any_of("="));  if (vecT.size() == 2)  {  vecT[0] = vecT[0].substr(vecT[0].find_first_not_of(' '), vecT[0].find_last_not_of(' '));  mapKeyValue[vecT[0]] = vecT[1];  }//end if  }//end for  }wstring s2ws_UTF8ToGBK(string sUTF8){std::wstring_convert<std::codecvt_utf8<wchar_t>> conv;std::wstring wsR =  conv.from_bytes(sUTF8);std::locale::global(std::locale("Chinese-simplified"));wstringstream wss;wss<<wsR;return wss.str();}std::string UTF8ToGBK( const std::string &strUTF8 ){try{std::wstring gbk = s2ws_UTF8ToGBK(strUTF8);std::string sGBK = ws2s_gbk(gbk);return sGBK;}catch (...){}return "";}std::string GBKToUTF8(const std::string& gbk)  {  std::string strOutUTF8 = "";  WCHAR * str1;  int n = MultiByteToWideChar(CP_ACP, 0, gbk.c_str(), -1, NULL, 0);  str1 = new WCHAR[n];  MultiByteToWideChar(CP_ACP, 0, gbk.c_str(), -1, str1, n);  n = WideCharToMultiByte(CP_UTF8, 0, str1, -1, NULL, 0, NULL, NULL);  char * str2 = new char[n];  WideCharToMultiByte(CP_UTF8, 0, str1, -1, str2, n, NULL, NULL);  strOutUTF8 = str2;  delete[]str1;  str1 = NULL;  delete[]str2;  str2 = NULL;  return strOutUTF8;  }std::wstring s2ws_gbk( const std::string& s ){int len;  int slength = (int)s.length() + 1;  len = MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, 0, 0);  wchar_t* buf = new wchar_t[len];  MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, buf, len);  std::wstring r(buf);  delete[] buf;  return r;  }std::string ws2s_gbk(const std::wstring& ws)  {  std::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);std::string result = _Dest;delete []_Dest;setlocale(LC_ALL, curLocale.c_str());return result;}void  string_replace( std::wstring &strBig, const std::wstring &strsrc, const std::wstring &strdst )  {  std::wstring::size_type pos = 0;  std::wstring::size_type srclen = strsrc.size();  std::wstring::size_type dstlen = strdst.size();  while( (pos=strBig.find(strsrc, pos)) != std::string::npos )  {  strBig.replace( pos, srclen, strdst );  pos += dstlen;  }  }std::string delHeapMemory( char *p ){std::string temp = p;delete p;return temp;}BOOL UrlEncode(const char* szSrc, char* pBuf, int cbBufLen, BOOL bUpperCase)  {  if (szSrc == NULL || pBuf == NULL || cbBufLen <= 0)  return FALSE;  size_t len_ascii = strlen(szSrc);  if (len_ascii == 0)  {  pBuf[0] = 0;  return TRUE;  }  //先转换到UTF-8  char baseChar = bUpperCase ? 'A' : 'a';  int cchWideChar = MultiByteToWideChar(CP_ACP, 0, szSrc, len_ascii, NULL, 0);  LPWSTR pUnicode = (LPWSTR)malloc((cchWideChar + 1) * sizeof(WCHAR));  if (pUnicode == NULL)  return FALSE;  MultiByteToWideChar(CP_ACP, 0, szSrc, len_ascii, pUnicode, cchWideChar + 1);  int cbUTF8 = WideCharToMultiByte(CP_UTF8, 0, pUnicode, cchWideChar, NULL, 0, NULL, NULL);  LPSTR pUTF8 = (LPSTR)malloc((cbUTF8 + 1) * sizeof(CHAR));  if (pUTF8 == NULL)  {  free(pUnicode);  return FALSE;  }  WideCharToMultiByte(CP_UTF8, 0, pUnicode, cchWideChar, pUTF8, cbUTF8 + 1, NULL, NULL);  pUTF8[cbUTF8] = '\0';  unsigned char c;  int cbDest = 0; //累加  unsigned char *pSrc = (unsigned char*)pUTF8;  unsigned char *pDest = (unsigned char*)pBuf;  while (*pSrc && cbDest < cbBufLen - 1)  {  c = *pSrc;  if (isalpha(c) || isdigit(c) || c == '-' || c == '.' || c == '~')  {  *pDest = c;  ++pDest;  ++cbDest;  }  else if (c == ' ')  {  *pDest = '+';  ++pDest;  ++cbDest;  }  else  {  //检查缓冲区大小是否够用？  if (cbDest + 3 > cbBufLen - 1)  break;  pDest[0] = '%';  pDest[1] = (c >= 0xA0) ? ((c >> 4) - 10 + baseChar) : ((c >> 4) + '0');  pDest[2] = ((c & 0xF) >= 0xA) ? ((c & 0xF) - 10 + baseChar) : ((c & 0xF) + '0');  pDest += 3;  cbDest += 3;  }  ++pSrc;  }  //null-terminator  *pDest = '\0';  free(pUnicode);  free(pUTF8);  return TRUE;  }  string encodeURI(string strSrc)  {  char *buf[512];  memset(buf, 0, sizeof(buf));  UrlEncode(strSrc.c_str(), (char*)(buf), sizeof(buf), TRUE);  string dst((char *)buf);  return dst;  }  };

字符串转大写（或小写）

http://www.cnblogs.com/mmix2009/archive/2013/07/19/3200150.html