编码比原始文本大:如何获取0和1的字符串并将其作为实际字节写入文件

最后我想到了

    unsigned char str_to_byte(std::string s){
    std::bitset<8> b(s);
    return static_cast<unsigned char> (b.to_ulong());
}


    void write(std::string s,std::ostream& out)
{
    size_t len = s.length();
    std::string tstring;
    unsigned char c;
    if (len < 8){
        tstring = pad_string(s, 8);
        c = str_to_byte(tstring);
        //std::cout << tstring << std::endl;
        out << c;
        return;
    }
    size_t i = 0 ;
    for (; i < len; i+=8){
        tstring = s.substr(i,8);
        //std::cout << tstring << std::endl;
        c = str_to_byte(tstring);
        out << c;
    }
    if (i != len){
        i = i-8;
        tstring = pad_string(s.substr(i,8),8);
        //std::cout << tstring << std::endl;
        c = str_to_byte(tstring);
        out << c;
    }
}