unix 时间戳与文本转换

Unix时间戳是指从1970年1月1日（UTC/GMT的午夜）开始所经过的秒数，不考虑闰秒。它是一种用于计算机系统中记录时间的方式，可以用于表示某个特定时刻的绝对时间。Unix时间戳在很多计算机系统和编程语言中被广泛使用，包括Unix、Linux、Java等。它以一个32位或64位的整数的形式来存储，而不是普通的日期和时间格式。在软件开发中，Unix时间戳能够有效缩减程序的体积，只要一个整数形式就可以表示时间。

需要注意的是，Unix时间戳有其局限性，例如32位Unix时间戳会在2038年遇到所谓的“2038年问题”或“Y2038”，届时其最大值将被达到，之后将从零开始计算，导致时间戳溢出。因此，现代系统多采用64位Unix时间戳以避免此类问题。

获取 Unix 时间戳代码示例

以下是一些常见编程语言中获取当前 Unix 时间戳的代码示例：

Python

import time; 
timestamp = int(time.time())

JavaScript (Node.js)

const timestamp = Math.round(Date.now() / 1000);

Java

long timestamp = System.currentTimeMillis() / 1000;

C++

#include <chrono>; 
#include <ctime>; 
auto now = std::chrono::system_clock::now(); 
std::time_t timestamp = std::chrono::system_clock::to_time_t(now);

C

long timestamp = (long)(DateTime.UtcNow - new DateTime(1970, 1, 1)).TotalSeconds;

PHP

$timestamp = time();

Ruby

timestamp = Time.now.to_i

Go

import "time"; 
timestamp := time.Now().Unix()

Rust

use std::time; 
let timestamp = time::SystemTime::now().duration_since(time::UNIX_EPOCH).unwrap().as_secs();

Swift

let timestamp = Int(Date().timeIntervalSince1970)

Unix 时间戳转字符串代码示例

以下是一些常见编程语言中将Unix时间戳转换为字符串（通常为可读的日期和时间格式）的代码示例：

Python

import time

timestamp = 1626739200  # 示例Unix时间戳
formatted_time = time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(timestamp))
print(formatted_time)

JavaScript (Node.js)

const timestamp = 1626739200;  // 示例Unix时间戳
const formattedTime = new Date(timestamp * 1000).toISOString().slice(0, 19).replace('T', ' ');
console.log(formattedTime);

Java

long timestamp = 1626739200L;  // 示例Unix时间戳
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
sdf.setTimeZone(TimeZone.getDefault());
String formattedTime = sdf.format(new Date(timestamp * 1000));
System.out.println(formattedTime);

C++ (使用C++11标准库)

#include <iostream>
#include <ctime>
#include <iomanip>
#include <sstream>

int main() {
    time_t timestamp = 1626739200;  // 示例Unix时间戳
    std::tm* localTime = std::localtime(&timestamp);
    std::ostringstream oss;
    oss << std::put_time(localTime, "%Y-%m-%d %H:%M:%S");
    std::string formattedTime = oss.str();
    std::cout << formattedTime << std::endl;
    return 0;
}

C

using System;

class Program {
    static void Main() {
        long timestamp = 1626739200;  // 示例Unix时间戳
        DateTime dateTime = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc).AddSeconds(timestamp);
        string formattedTime = dateTime.ToString("yyyy-MM-dd HH:mm:ss");
        Console.WriteLine(formattedTime);
    }
}

PHP

$timestamp = 1626739200;  // 示例Unix时间戳
$formattedTime = date('Y-m-d H:i:s', $timestamp);
echo $formattedTime;

Ruby

timestamp = 1626739200  # 示例Unix时间戳
formatted_time = Time.at(timestamp).strftime('%Y-%m-%d %H:%M:%S')
puts formatted_time

Go

package main

import (
    "fmt"
    "time"
)

func main() {
    timestamp := int64(1626739200)  // 示例Unix时间戳
    t := time.Unix(timestamp, 0)
    formattedTime := t.Format("2006-01-02 15:04:05")
    fmt.Println(formattedTime)
}

Rust

use std::time;

fn main() {
    let timestamp = 1626739200;  // 示例Unix时间戳
    let dt = time::Unix(timestamp);
    let formatted_time = dt.format("%Y-%m-%d %H:%M:%S").to_string();
    println!("{}", formatted_time);
}

Swift

let timestamp = 1626739200  // 示例Unix时间戳
let date = Date(timeIntervalSince1970: TimeInterval(timestamp))
let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
formatter.timeZone = TimeZone.current
let formattedTime = formatter.string(from: date)
print(formattedTime)

时间字符串转 Unix 时间戳代码示例

以下是一些常见编程语言中将日期时间字符串转换为Unix时间戳的代码示例：

Python

from datetime import datetime

date_string = "2021-07-20 12:34:56"  # 示例日期时间字符串
date_format = "%Y-%m-%d %H:%M:%S"
timestamp = int(datetime.strptime(date_string, date_format).timestamp())
print(timestamp)

JavaScript (Node.js)

const dateString = "2021-07-20T12:34:56";  // 示例日期时间字符串，注意ISO格式
const timestamp = new Date(dateString).getTime() / 1000;
console.log(timestamp);

Java

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Main {
    public static void main(String[] args) {
        String dateString = "2021-07-20 12:34:56";  // 示例日期时间字符串
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        try {
            Date date = sdf.parse(dateString);
            long timestamp = date.getTime() / 1000;
            System.out.println(timestamp);
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }
}

C++ (使用C++11标准库)

#include <iostream>
#include <ctime>
#include <sstream>
#include <iomanip>

int main() {
    std::string dateString = "2021-07-20 12:34:56";  // 示例日期时间字符串
    std::istringstream iss(dateString);
    std::tm tm{};
    iss >> std::get_time(&tm, "%Y-%m-%d %H:%M:%S");
    std::time_t timestamp = std::mktime(&tm);
    std::cout << timestamp << std::endl;
    return 0;
}

C

using System;
using System.Globalization;

class Program {
    static void Main() {
        string dateString = "2021-07-20 12:34:56";  // 示例日期时间字符串
        DateTime date = DateTime.ParseExact(dateString, "yyyy-MM-dd HH:mm:ss", CultureInfo.InvariantCulture);
        long timestamp = (long)date.ToUniversalTime().Subtract(new DateTime(1970, 1, 1)).TotalSeconds;
        Console.WriteLine(timestamp);
    }
}

PHP

$dateString = "2021-07-20 12:34:56";  // 示例日期时间字符串
$timestamp = strtotime($dateString);
echo $timestamp;

Ruby

date_string = "2021-07-20 12:34:56"  # 示例日期时间字符串
timestamp = DateTime.parse(date_string).to_time.to_i
puts timestamp

Go

package main

import (
    "fmt"
    "time"
)

func main() {
    dateString := "2021-07-20 12:34:56"  // 示例日期时间字符串
    layout := "2006-01-02 15:04:05"
    t, err := time.Parse(layout, dateString)
    if err != nil {
        panic(err)
    }
    timestamp := t.Unix()
    fmt.Println(timestamp)
}

Rust

use std::time;
use chrono::DateTime;
use chrono::NaiveDateTime;
use chrono::Utc;

fn main() {
    let date_string = "2021-07-20 12:34:56".to_string();  // 示例日期时间字符串
    let dt = DateTime::<Utc>::parse_from_str(&date_string, "%Y-%m-%d %H:%M:%S").unwrap();
    let timestamp = dt.with_time_zone(&Utc).timestamp();
    println!("{}", timestamp);
}