Posted on 2019-11-27 18:36
魔のkyo 阅读(225)
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C++
Windows上参考
http://www.cnitblog.com/luckydmz/archive/2010/03/03/64458.html
#include <iconv.h>
#include <cstring>
#include <string>
#include <iostream>
class EncodingConvertor
{
public:
// "UTF-8", "GBK"
EncodingConvertor(const char* toEncoding, const char* fromEncoding)
{
_iconv = iconv_open(toEncoding, fromEncoding);
}
std::string convert(const char* in)
{
constexpr size_t BLOCK_SIZE = 1024; // iconv可以分块转换，对于特别长的字符串（特别大的文件）
size_t inlen = strlen(in);
size_t outbuflen = std::max(inlen * 2, BLOCK_SIZE);
const char* pin = in;
char* outbuf = (char*)malloc(outbuflen);
char* pout = outbuf;
size_t ret = 0;
do {
size_t perlen = BLOCK_SIZE;
if(pout + perlen > outbuf + outbuflen - 1)
{ // 如果outbuf后面剩余空间不足一个转换块大小，就重新分配空间
int pout_offset = pout - outbuf;
outbuflen = std::max(outbuflen * 2, BLOCK_SIZE);
outbuf = (char*)realloc(outbuf, outbuflen);
pout = outbuf + pout_offset; // outbuf可能指向新地址，所以要把pout偏移过去
}
ret = iconv(_iconv, (char**)&pin, &inlen, &pout, &perlen);
if(perlen == BLOCK_SIZE)
{ // 转移前后perlen没有变化应该是出错了
outbuf[0] = 0;
break;
}
} while(ret == -1);
*pout = 0;
std::string r(outbuf);
free(outbuf);
return r;
}
~EncodingConvertor()
{
iconv_close(_iconv);
}
private:
iconv_t _iconv;
};
int main()
{
EncodingConvertor convertor("UTF-8", "GBK");
std::string s = convertor.convert("GBK string");
std::cout << s << std::endl;
return 0;
}