How to convert time into timestamp in php? Introduction to three methods

A timestamp is a simple way for computer systems to record dates and times. In PHP, you can calculate time differences, retrieve data, and more by converting datetimes to timestamps. This article will introduce how to convert time to timestamp in PHP.

1. date() function

In PHP, you can use the date() function to convert any date and time format into a timestamp. The syntax of this function is as follows:

date(string $format[, int $timestamp])

Among them, the $format parameter represents the date and time format. The meanings of the letters that can be used are as follows:

• Y, 4-digit year;
• m, month, if there are less than two digits, add 0 in front;
• d, date , add 0 before the number is less than two digits;
• H, hour, 24-hour format, add 0 before the number is less than two digits;
• i , minutes, add 0 before the number is less than two digits;
• s, seconds, add 0 before the number is less than two digits.

$timestampThe parameter represents the timestamp and is an optional parameter. If this parameter is not provided, the current date and time is used by default.

The following is an example for converting the current date and time to a timestamp:

<?php     $date = date(&#39;Y-m-d H:i:s&#39;);
    $timestamp = strtotime($date);
?>

where the $date variable stores the current date and time, passed date() Function converts to the specified format. Then, convert that date and time to a timestamp using the strtotime() function. Finally, store the timestamp in the $timestamp variable.

2. strtotime() function

strtotime() function is a very useful time function in PHP, which can Convert any text date and time to a timestamp. The syntax of this function is as follows:

strtotime(string $time[, int $now])

Among them, the $time parameter indicates the date and time format to be converted to a timestamp. The $now parameter represents the offset (in seconds) used to calculate the month and year. This can be set manually. If not, the system time will be calculated as an offset.

The following is an example of converting a specified date and time into a timestamp:

<?php     $time = &#39;2022-10-10 10:10:10&#39;;
    $timestamp = strtotime($time);
?>

Among them, the $time variable stores the specified date and time. Then, use the strtotime() function to convert that date and time to a timestamp. Finally, store the timestamp in the $timestamp variable.

3. DateTime class

In PHP, you can also use the DateTime class to convert dates and times into timestamps. This class provides various methods for more convenient processing of dates and times. The following is an example of converting a specified date and time into a timestamp:

<?php     $time = &#39;2022-10-10 10:10:10&#39;;
    $datetime = new DateTime($time);
    $timestamp = $datetime->getTimestamp();
?>

Among them, the $time variable stores the specified date and time. Then, a DateTime object is created, passing the date and time to the constructor. Finally, use the getTimestamp() method to convert that date and time into a timestamp. Finally, store the timestamp in the $timestamp variable.

Summary:

This article introduces how to convert date and time to timestamp in PHP. Either method converts a specified date and time into a number that represents the number of seconds elapsed since January 1, 1970 00:00:00 UTC (Coordinated Universal Time). By mastering these methods, you can work with dates and times more efficiently in PHP.

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