PHP Date and Time

The PHP date() function serves for formatting a date or time.

The PHP date() method converts timestamp to a date and time that is more legible.

Syntax :-

date(format,timestamp)

A timestamp is a character sequence that indicates the date and/or time at which a given event took place.

The needed date() format argument defines how the date is formatted (or time).

The following are some examples of date characters :-

• d - The month's day is represented by this symbol (01 to 31).
• m - A month is represented by this symbol (01 to 12).
• Y - A year is represented by this symbol (in four digits).
• l (lowercase 'L') - The weekday is represented by this symbol.

Additional formatting can be added by inserting characters such as "/", ".", or "-" between the text.

Example :- Today's date is formatted three different ways in the example below :

<?php
echo "Today is " . date("Y/m/d") . "<br />";
echo "Today is " . date("Y.m.d") . "<br />";
echo "Today is " . date("Y-m-d") . "<br />";
echo "Today is " . date("l");
?>

Output :-

To automatically change the patent year from your website, use the date() function :

Example :- To keep your website's copyright year current, use the date() function :

&copy; 2010-<?php echo date("Y");?>

Output :-

Here are some examples of characters that are often used to indicate the passage of time :

• H - An hour is formatted in a 24-hour format (00 to 23).
• h - Leading zeros are used in a 12-hour format (01 to 12).
• i - Leading zeros in minutes (00 to 59).
• s - Leading zeros in seconds (00 to 59).
• a - Ante meridiem and Post meridiem are both written in lowercase letters (am or pm).

Example :- The following example displays the current time in the format you specify :-

<?php
echo "The time is " . date("H:i");
?>

Output :-

It should be noted that the PHP date() method returns the server's current date and time!.

If the time returned by the code is incorrect, it is most likely due to your server being located in another country or being configured for a different timezone.

So you may set the timezone you wish to utilize if you need to be right according to one particular region.

Example :- The example above sets "America/New York" to the time zone, and then the current time is in the format requested :

<?php
date_default_timezone_set("America/New_York");
echo "The time is " . date("h:i:sa");
?>

The following example changes the timezone to "America/New York" and then prints the current time in the format given.

For a date, the Unix timestamp is returned with the PHP mktime() feature. The time template for Unix includes the number of seconds (1 January 1970 00:00:00 GMT) between the Unix Epoque and the time.

Syntax :-

mktime(hour, minute, second, month, day, year)

Example :- The following example uses the date() function to generate a date and time from the mktime() method's parameters :

<?php
$d=mktime(11, 14, 54, 8, 12, 2014);
echo "Created date is " . date("Y-m-d h:i:sa", $d);
?>

PHP strtotime() is used to convert a date string understandable by humans to a Unix timestamp (the number of seconds since January 1 1970 00:00:00 GMT).

Syntax :-

strtotime(time, now)

Example 1 :- From the strtotime() function, the following example creates a date and time :

<?php
$d=strtotime("10:30pm April 15 2014");
echo "Created date is " . date("Y-m-d h:i:sa", $d);
?>

Example 2 :- PHP does a great job of converting a string to a date, allowing you to use a variety of values :

<?php
$d=strtotime("tomorrow");
echo date("Y-m-d h:i:sa", $d) . "<br />";
$d=strtotime("next Saturday");
echo date("Y-m-d h:i:sa", $d) . "<br />";
$d=strtotime("+3 Months");
echo date("Y-m-d h:i:sa", $d) . "<br />";
?>

Strtotime() isn't ideal though, so remember to verify the strings.

Example 1 :- The following example shows the dates for the next six Saturdays :

<?php
$startdate=strtotime("Saturday");
$enddate=strtotime("+6 weeks", $startdate);
while ($startdate < $enddate) {
  echo date("M d", $startdate) . "<br />";
  $startdate = strtotime("+1 week", $startdate);
}
?>

Example 2 :- The following example calculates the number of days remaining till July 4th :

<?php
$d1=strtotime("July 04");
$d2=ceil(($d1-time())/60/60/24);
echo "There are " . $d2 ." days until 4th of July.";
?>