How to convert time to timestamp in php? Method introduction

What are the benefits of using timestamps in PHP? Timestamps can be used in almost all programming languages. Not only can the time be converted into a readable string, but the string can also be converted into a computable numerical representation, so that time operations can be conveniently performed in the program. There are many ways to get the current time in PHP, but the most commonly used method is to convert the current time into a timestamp. This article details how to convert time to timestamp using PHP.

1. The concept of timestamp

A timestamp is an integer that represents the number of seconds between a specific time. On Unix systems, timestamps are calculated from January 1, 1970 at 00:00:00. Therefore, the timestamp of 00:00:00 on January 1, 1970 is 0.

2. Basic usage of PHP timestamp

The method to convert time to timestamp is very simple. PHP has a built-in time() function that can be used to get the timestamp of the current time (in seconds).

$timestamp = time();
echo $timestamp;

This code will output the timestamp of the current time. If you need to get a more detailed timestamp, you can use the microtime() function, which will return the number of seconds and microseconds of the current time. The number of seconds is the same as a regular timestamp, and the number of microseconds is a decimal represented by a six-digit number that can be accurate to the microsecond level.

$microtime = microtime(true);
echo $microtime;

3. Convert time to timestamp

There are many ways to convert time to timestamp in PHP. Below we will introduce several practical methods. Here, we assume that the format for converting time to timestamp is Y-m-d H:i:s, which is the commonly used date and time format.

// 方法1 ： strtotime() 函数
$dateStr = '2022-01-01 00:00:00';
$timestamp = strtotime($dateStr);
echo $timestamp;

In the above code, the strtotime() function can convert a date string that meets the format requirements into a timestamp. This function also supports more diverse date string conversions, such as yesterday or next week, etc.

// 方法2 ： DateTime 类
$dateStr = '2022-01-01 00:00:00';
$date = DateTime::createFromFormat('Y-m-d H:i:s', $dateStr);
$timestamp = $date->getTimestamp();
echo $timestamp;

In the second method, we use PHP’s built-in date processing class DateTime. This class can control the date and time format more precisely and facilitate some complex date and time operations in the program.

If you need to convert a timestamp into a date string, you can use the date() function. This function accepts two parameters, the first is the datetime format and the second is the converted timestamp. For example:

$timestamp = time();
$dateStr = date('Y-m-d H:i:s', $timestamp);
echo $dateStr;

4. Summary

This article introduces the method of converting time to timestamp in PHP. These methods can help us handle dates and times more flexibly in actual development, providing more possibilities and convenience for program running.

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