C++时间转换成时间戳形式

时间格式："2022-07-11_19:03:56.458"

C++98

#include <iostream>
#include <chrono>
#include <ctime>

int main() {
    std::string date_time_str = "2022-07-11_19:03:56.458";
    int year, month, day, hour, minute, second;
    sscanf(date_time_str.c_str(), "%d-%d-%d_%d:%d:%d", &year, &month, &day, &hour, &minute, &second);
    std::tm date_time = {};
    date_time.tm_year = year - 1900;
    date_time.tm_mon = month - 1;
    date_time.tm_mday = day;
    date_time.tm_hour = hour;
    date_time.tm_min = minute;
    date_time.tm_sec = second;
    auto timestamp = std::chrono::system_clock::from_time_t(std::mktime(&date_time));
    auto duration = timestamp.time_since_epoch();
    auto millis = std::chrono::duration_cast<std::chrono::milliseconds>(duration).count();
    std::cout << millis << "\n";
    return 0;
}

C++14

#include <iostream>
#include <chrono>
#include <ctime>

int main() {
    std::string date_time_str = "2022-07-11_19:03:56.458";
    int year, month, day, hour, minute, second;
    sscanf_s(date_time_str.c_str(), "%d-%d-%d_%d:%d:%d", &year, &month, &day, &hour, &minute, &second);
    std::tm date_time = {};
    date_time.tm_year = year - 1900;
    date_time.tm_mon = month - 1;
    date_time.tm_mday = day;
    date_time.tm_hour = hour;
    date_time.tm_min = minute;
    date_time.tm_sec = second;
    auto timestamp = std::chrono::system_clock::from_time_t(std::mktime(&date_time));
    auto duration = timestamp.time_since_epoch();
    auto millis = std::chrono::duration_cast<std::chrono::milliseconds>(duration).count();
    std::cout << millis << "\n";
    return 0;
}