1 #include <iconv.h> 2  3 int code_convert(char *from_charset,char *to_charset,char *inbuf,int inlen,char *outbuf,int outlen) 4 { 5         iconv_t cd; 6         int rc; 7         char **pin = &inbuf; 8         char **pout = &outbuf; 9 10         cd = iconv_open(to_charset,from_charset);11         if (cd==0)12                 return -1;13         memset(outbuf,0,outlen);14         if (iconv(cd,pin,&inlen,pout,&outlen) == -1)15                 return -1;16         iconv_close(cd);17         return 0;18 }19 20 int u2g(char *inbuf,int inlen,char *outbuf,int outlen)21 {22         return code_convert("utf-8","gb2312",inbuf,inlen,outbuf,outlen);23 }24 25 int g2u(char *inbuf,size_t inlen,char *outbuf,size_t outlen)26 {27         return code_convert("gb2312","utf-8",inbuf,inlen,outbuf,outlen);28 }

其中iconv函数族的头文件是iconv.h,使用前需包含之。#include <iconv.h>iconv函数族有三个函数,原型如下:(1) iconv_t iconv_open(const char *tocode, const char *fromcode);此函数说明将要进行哪两种编码的转换,tocode是目标编码,fromcode是原编码,该函数返回一个转换句柄,供以下两个函数使用。(2) size_t iconv(iconv_t cd,char **inbuf,size_t *inbytesleft,char **outbuf,size_t *outbytesleft);此函数从inbuf中读取字符,转换后输出到outbuf中,inbytesleft用以记录还未转换的字符数,outbytesleft用以记录输出缓冲的剩余空间。(3) int iconv_close(iconv_t cd);此函数用于关闭转换句柄,释放资源。

 1     #include <iostream>   2     #include <string>   3     #include <fstream>   4     #include <windows.h>    5        6     using namespace std;   7        8     string GBKToUTF8(const std::string& strGBK)   9     {  10         string strOutUTF8 = "";  11         WCHAR * str1;  12         int n = MultiByteToWideChar(CP_ACP, 0, strGBK.c_str(), -1, NULL, 0);  13         str1 = new WCHAR[n];  14         MultiByteToWideChar(CP_ACP, 0, strGBK.c_str(), -1, str1, n);  15         n = WideCharToMultiByte(CP_UTF8, 0, str1, -1, NULL, 0, NULL, NULL);  16         char * str2 = new char[n];  17         WideCharToMultiByte(CP_UTF8, 0, str1, -1, str2, n, NULL, NULL);  18         strOutUTF8 = str2;  19         delete[]str1;  20         str1 = NULL;  21         delete[]str2;  22         str2 = NULL;  23         return strOutUTF8;  24     }  25       26     string UTF8ToGBK(const std::string& strUTF8)  27     {  28         int len = MultiByteToWideChar(CP_UTF8, 0, strUTF8.c_str(), -1, NULL, 0);  29         unsigned short * wszGBK = new unsigned short[len + 1];  30         memset(wszGBK, 0, len * 2 + 2);  31         MultiByteToWideChar(CP_UTF8, 0, (LPCTSTR)strUTF8.c_str(), -1, wszGBK, len);  32       33         len = WideCharToMultiByte(CP_ACP, 0, wszGBK, -1, NULL, 0, NULL, NULL);  34         char *szGBK = new char[len + 1];  35         memset(szGBK, 0, len + 1);  36         WideCharToMultiByte(CP_ACP,0, wszGBK, -1, szGBK, len, NULL, NULL);  37         //strUTF8 = szGBK;  38         std::string strTemp(szGBK);  39         delete[]szGBK;  40         delete[]wszGBK;  41         return strTemp;  42     }  43       44     int _tmain(int argc, _TCHAR* argv[])  45     {  46         string test("我们中国是个强大的名族，强大的动力来自每个人的支持");  47         fstream output("test.txt",ios_base::out | ios_base::app);  48         output << GBKToUTF8(test);  49         //system("iconv -f GBK -t utf-8");  50         return 0;  51     }