Understand the two representations of timestamps in PHP

PHP timestamps measure the number of seconds from January 1, 1970 00:00:00 UTC to the current time. It is used to record and calculate date and time in PHP.

In PHP, a timestamp is an integer representing the number of seconds since the Unix epoch (i.e. January 1, 1970 00:00:00 UTC). Therefore, it can be used to convert and compare times.

PHP timestamps are 10 or 13 digits, depending on the functions and operations used. In this article, we will look at the two representations of timestamps in PHP and how to use them in your code.

1. 10-digit timestamp

The 10-digit timestamp is the number of seconds since the Unix epoch, so it is suitable for representing future or past dates and times. In PHP, you can use the time() function to get the current timestamp. For example, the following code will return a 10-digit timestamp of the current time:

$timestamp = time();

Similarly, dates and times can be converted to 10-digit timestamps using the strtotime() function. For example, the following code will return a timestamp of 00:00:00 on October 10, 2021:

$timestamp = strtotime('2021-10-10');

You can convert a 10-digit timestamp to a date and time using the date() function in PHP. For example, the following code will format a date and time into year, month, day, hour, minute, and second using a 10-digit timestamp:

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

2. 13-digit timestamp

13-digit The timestamp is the number of milliseconds since the Unix epoch, so it is suitable for applications that require more precise time. In PHP, you can use the microtime() function to get the current 13-digit timestamp. For example, the following code will return the current 13-digit timestamp:

$timestamp = round(microtime(true) * 1000);

Similarly, a DateTime object can be used to obtain a 13-digit timestamp. For example, the following code will return a 13-digit timestamp at 00:00:00 on October 10, 2021:

$date = new DateTime('2021-10-10');
$timestamp = $date->format('U.u') * 1000;

You can convert a 13-digit timestamp to a date and time using the date() function in PHP . For example, the following code will format a date and time into year, month, day, hour, minute and second using a 13-digit timestamp: Date and time applications are crucial. In this article, we discussed two representations of timestamps in PHP: 10-digit timestamps and 13-digit timestamps. Either way, using timestamps makes it easy to do date and time calculations and comparisons in PHP.

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