c++ 常用功能实现总结

Posted 2021-11-09 长虹剑

基础

类型转换

using T = std::vector<std::vector<unsigned char>>*;
video_bytes = reinterpret_cast< T >( video_data );

模块

中文字符分隔

来自

std::vector<std::string> split_chinese(std::string s) {
    std::vector<std::string> t;
    for (size_t i = 0; i < s.length();)
    {
        int cplen = 1;
        // 以下的几个if，要参考这里 https://en.wikipedia.org/wiki/UTF-8#Description
        if ((s[i] & 0xf8) == 0xf0)      // 11111000, 11110000
            cplen = 4;
        else if ((s[i] & 0xf0) == 0xe0) // 11100000
            cplen = 3;
        else if ((s[i] & 0xe0) == 0xc0) // 11000000
            cplen = 2;
        if ((i + cplen) > s.length())
            cplen = 1;
        t.push_back(s.substr(i, cplen));
        i += cplen;
    }
    return t;
}