c++ UrlEncode 实现

unsigned int utf8_decode( char *s, unsigned int *pi ) { unsigned int c; int i = *pi; /* one digit utf-8 */ if ((s[i] & 128)== 0 ) { c = (unsigned int) s[i]; i += 1; } else if ((s[i] & 224)== 192 ) { /* 110xxxxx & 111xxxxx == 110xxxxx */ c = (( (unsigned int) s[i] & 31 ) << 6) + ( (unsigned int) s[i+1] & 63 ); i += 2; } else if ((s[i] & 240)== 224 ) { /* 1110xxxx & 1111xxxx == 1110xxxx */ c = ( ( (unsigned int) s[i] & 15 ) << 12 ) + ( ( (unsigned int) s[i+1] & 63 ) << 6 ) + ( (unsigned int) s[i+2] & 63 ); i += 3; } else if ((s[i] & 248)== 240 ) { /* 11110xxx & 11111xxx == 11110xxx */ c = ( ( (unsigned int) s[i] & 7 ) << 18 ) + ( ( (unsigned int) s[i+1] & 63 ) << 12 ) + ( ( (unsigned int) s[i+2] & 63 ) << 6 ) + ( (unsigned int) s[i+3] & 63 ); i+= 4; } else if ((s[i] & 252)== 248 ) { /* 111110xx & 111111xx == 111110xx */ c = ( ( (unsigned int) s[i] & 3 ) << 24 ) + ( ( (unsigned int) s[i+1] & 63 ) << 18 ) + ( ( (unsigned int) s[i+2] & 63 ) << 12 ) + ( ( (unsigned int) s[i+3] & 63 ) << 6 ) + ( (unsigned int) s[i+4] & 63 ); i += 5; } else if ((s[i] & 254)== 252 ) { /* 1111110x & 1111111x == 1111110x */ c = ( ( (unsigned int) s[i] & 1 ) << 30 ) + ( ( (unsigned int) s[i+1] & 63 ) << 24 ) + ( ( (unsigned int) s[i+2] & 63 ) << 18 ) + ( ( (unsigned int) s[i+3] & 63 ) << 12 ) + ( ( (unsigned int) s[i+4] & 63 ) << 6 ) + ( (unsigned int) s[i+5] & 63 ); i += 6; } else { c = '?'; i++; } *pi = i; return c; } std::string UrlEncode(const std::string& src) { static char hex[] = "0123456789ABCDEF"; std::string dst; for (size_t i = 0; i < src.size(); i++) { unsigned char ch = src[i]; if (isalnum(ch)) { dst += ch; } else if (src[i] == ' ') { dst += '+'; } else { unsigned char c = static_cast<unsigned char>(src[i]); dst += '%'; dst += hex[c / 16]; dst += hex[c % 16]; } } return dst; } std::string UrlDecode(const std::string& src) { std::string dst, dsturl; int srclen = src.size(); for (size_t i = 0; i < srclen; i++) { if (src[i] == '%') { if(isxdigit(src[i + 1]) && isxdigit(src[i + 2])) { char c1 = src[++i]; char c2 = src[++i]; c1 = c1 - 48 - ((c1 >= 'A') ? 7 : 0) - ((c1 >= 'a') ? 32 : 0); c2 = c2 - 48 - ((c2 >= 'A') ? 7 : 0) - ((c2 >= 'a') ? 32 : 0); dst += (unsigned char)(c1 * 16 + c2); } } else if (src[i] == '+') { dst += ' '; } else { dst += src[i]; } } int len = dst.size(); for(unsigned int pos = 0; pos < len;) { unsigned int nvalue = utf8_decode((char *)dst.c_str(), &pos); dsturl += (unsigned char)nvalue; } return dsturl; }