How to convert year, month and day format into different formats in PHP

In PHP, date and time formats are very common and necessary. However, sometimes we need to convert different date formats to another date format, which requires the use of date format conversion functions. This article will introduce how to convert the year, month and day format into different formats in PHP.

There are many built-in functions in PHP that can be used to handle dates and times. Some of these functions can convert dates and times from one format to another. Here are some of the most commonly used date format conversion functions:

1. date() function

The date() function is a built-in function in PHP for formatting dates. The function uses a format string to specify the date format and passes the date and time as arguments. Here are some common options for format strings:

• Y: Four-digit year
• y: Two-digit year
• m: Month (With leading zeros)
• n: Month (without leading zeros)
• d: Day (with leading zeros)
• j: Day (without leading zeros)
• H: 24-hour time (with leading zeros)
• h: 12-hour time (with leading zeros)
• i: Minutes (with leading zeros)
• s: Seconds (with leading zeros)
• A: Uppercase AM or PM
• a: Lowercase AM or PM

The following is a date Example of conversion to yyyy-mm-dd format:

$date = '2019-10-15';
$new_date = date('Y-m-d', strtotime($date));
echo $new_date; // 输出2019-10-15

2. strtotime() function

The strtotime() function is a built-in function in PHP for parsing date strings . It can convert one date format to another and return a Unix timestamp. Here is an example of converting a date to a Unix timestamp:

$date = '2019-10-15';
$timestamp = strtotime($date);
echo $timestamp; // 输出1571126400

3. DateTime Class

The DateTime class is an object-oriented way of handling dates and times in PHP. It provides two classes: DateTime and DateTimeImmutable. Among them, the DateTime class represents a mutable date and time object, and the DateTimeImmutable class represents an immutable date and time object.

Use the DateTime class to easily convert different date formats to another date format. The following is an example of converting a date into yyyy-mm-dd format:

$date = '2019-10-15';
$datetime = new DateTime($date);
$new_date = $datetime->format('Y-m-d');
echo $new_date; // 输出2019-10-15

The above is a simple example of converting the year, month and day format into different formats in PHP. In practical applications, we can format date and time into any format we want according to actual needs.

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