我程序中用到的urldecode和base64decode,MD5

这里是base64decode和urldecode,Md5在附件中。因为我是在后台所以需要解码:
string Base64Decode(const char* Data,int DataByte,int& OutByte)
{
    //解码表
    const char DecodeTable[] =
    {
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        62, // '+'
        0, 0, 0,
        63, // '/'
        52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // '0'-'9'
        0, 0, 0, 0, 0, 0, 0,
        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
        13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // 'A'-'Z'
        0, 0, 0, 0, 0, 0,
        26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
        39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 // 'a'-'z'
    };
    //返回值
    string strDecode;
    int nValue;
    int i= 0;
    while (i < DataByte)
    {
        if (*Data != '\r' && *Data!='\n')
        {
            nValue = DecodeTable[*Data++] << 18;
            nValue += DecodeTable[*Data++] << 12;
            strDecode+=(nValue & 0x00FF0000) >> 16;
            OutByte++;
            if (*Data != '=')
            {
                nValue += DecodeTable[*Data++] << 6;
                strDecode+=(nValue & 0x0000FF00) >> 8;
                OutByte++;
                if (*Data != '=')
                {
                    nValue += DecodeTable[*Data++];
                    strDecode+=nValue & 0x000000FF;
                    OutByte++;
                }
            }
            i += 4;
        }
        else// 回车换行,跳过
        {
            Data++;
            i++;
        }
     }
    return strDecode;
}


char * Cgi_urldecode(char * url)
        {
            int len = strlen(url);

            char *dest = url;
            char *data = url;

            while (len--) {
                if (*data == '+')
                    *dest = ' ';
                else if (*data == '%' && len >= 2 && isxdigit((int) *(data + 1)) && isxdigit((int) *(data + 2))) {

                    *dest = (char) htoi(data + 1);
                    data += 2;
                    len -= 2;
                } else
                    *dest = *data;
                data++;
                dest++;
            }
            *dest = '\0';
            return url ;
}

int htoi(char *s)
{
            int value;
            int c;

            c = ((unsigned char *)s)[0];
            if (isupper(c))
                c = tolower(c);
            value = (c >= '0' && c <= '9' ? c - '0' : c - 'a' + 10) * 16;

            c = ((unsigned char *)s)[1];
            if (isupper(c))
                c = tolower(c);
            value += c >= '0' && c <= '9' ? c - '0' : c - 'a' + 10;

            return (value);
}

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