url 中文及特殊字符转码

#include <ctype.h>

std::string UrlEncode(const std::string& szToEncode)

{

   std::string src = szToEncode;

    char hex[] = "0123456789ABCDEF";

    string dst;

 

    for (size_t i = 0; i < src.size(); ++i)

    {

        unsigned char cc = src[i];

        if (isascii(cc))

        {

            if (cc == ' ')

            {

                dst += "%20";

            }

            else

                dst += cc;

        }

        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& szToDecode)

{

    std::string result;

    int hex = 0;

    for (size_t i = 0; i < szToDecode.length(); ++i)

    {

        switch (szToDecode[i])

        {

        case '+':

            result += ' ';

            break;

        case '%':

            if (isxdigit(szToDecode[i + 1]) && isxdigit(szToDecode[i + 2]))

            {

                std::string hexStr = szToDecode.substr(i + 1, 2);

                hex = strtol(hexStr.c_str(), 0, 16);

                //字母和数字[0-9a-zA-Z]、一些特殊符号[$-_.+!*'(),] 、以及某些保留字[$&+,/:;=?@]

                //可以不经过编码直接用于URL

                if (!((hex >= 48 && hex <= 57) || //0-9

                    (hex >=97 && hex <= 122) ||   //a-z

                    (hex >=65 && hex <= 90) ||    //A-Z

                    //一些特殊符号及保留字[$-_.+!*'(),]  [$&+,/:;=?@]

                    hex == 0x21 || hex == 0x24 || hex == 0x26 || hex == 0x27 || hex == 0x28 || hex == 0x29

                    || hex == 0x2a || hex == 0x2b|| hex == 0x2c || hex == 0x2d || hex == 0x2e || hex == 0x2f

                    || hex == 0x3A || hex == 0x3B|| hex == 0x3D || hex == 0x3f || hex == 0x40 || hex == 0x5f

                    ))

                {

                    result += char(hex);

                    i += 2;

                }

                else result += '%';

            }else {

                result += '%';

            }

            break;

        default:

            result += szToDecode[i];

            break;

        }

    }

    return result;

}