PHP Date function

PHP datetime function Date ()

1, year-month-day
echo Date (' y-m-j ');
2007-02-6

echo Date (' y-n-j ');
07-2-6

Uppercase Y represents the year four digits, while lowercase y represents the two digits of the year;
Lowercase m represents the number of months (with leading), while lowercase n indicates no leading month number.

echo Date (' y-m-j ');
2007-feb-6

echo Date (' y-m-d ');
2007-02-06

The uppercase M represents the 3 abbreviated characters of the month, while the lowercase m represents the number of the month (with leading 0);
J with no uppercase, only lowercase J indicates the date of the month, no leading o, or lowercase D if a month with a leading is required.

echo Date (' y-m-j ');
2007-feb-6

echo Date (' Y-f-js ');
2007-february-6th

Uppercase M represents the 3 abbreviated characters of the month, while uppercase F indicates the full written English of the month. (No lowercase f)
Uppercase S represents the suffix of the date, such as "St", "nd", "rd", and "th", depending on the date number.

Summary:
Indicates that the year can be in uppercase Y and lowercase y;
Indicates that the month can be in uppercase F, uppercase M, lowercase m, and lowercase n (two ways of representing characters and numbers, respectively);
Indicates that the day can be in lowercase d and lowercase j, and uppercase s represents the suffix of the date.


2, Hours: minutes: seconds

By default, the PHP interpretation is displayed as "Greenwich Mean Time", which differs from our local time by 8 hours.

echo Date (' g:i:s a ');
5:56:57 am

echo Date (' H:i:s A ');
05:56:57 AM

The lowercase g represents a 12-hour system without a leading 0, while the lowercase h indicates a 12-hour system with a leading 0.
When using the 12-hour system, it is necessary to indicate that in the afternoon, lowercase a represents the lowercase "am" and "PM", and uppercase a denotes uppercase "AM" and "PM".

echo Date (' g:i:s ');
14:02:26

Uppercase G denotes 24-hour hours, but without preamble, and uppercase H for leading 24-hour hours

Summary:
The letter g means the hour without leading, the letter H denotes the hour with the preamble;
lowercase g, h for 12-hour system, uppercase G, h for 24-hour system.

3, Leap year, week, day

echo Date (' L ');
Leap Year: 0

echo Date (' L ');
Today is: Tuesday

echo Date (' D ');
Today is: Tue

Uppercase L Indicates whether this year is a leap years, a Boolean value that returns 1 for true, otherwise 0;
Lowercase L Indicates the day of the week in English full write (Tuesday);
Instead, use uppercase D to denote the 3-character abbreviation (TUE) of the day of the week.

echo Date (' W ');
Today's Week: 2

echo Date (' W ');
This week is the No. 06 week of the year.

The lowercase w represents the day of the week, and the numeric representation
Uppercase W indicates the number of weeks in a year

echo Date (' t ');
This month is 28 days

echo Date (' Z ');
Today is the 36th day of the year.

Lowercase t indicates the current month and how many days
Lowercase z indicates that today is the first day of the year

4, other

echo Date (' T ');
Utc
Capital T indicates the server's time zone setting

echo Date (' I ');
0
Uppercase I indicates whether the current is daylight saving time, returns 1 for true, otherwise 0

echo Date (' U ');
1170769424
The capital U represents the total number of seconds from January 1, 1970 to the present, which is the UNIX timestamp for the Unix time era.

echo Date (' C ');
2007-02-06t14:24:43+00:00
Lowercase C represents the ISO8601 date, the date format is YYYY-MM-DD, the letter T is used to interval the date and time, the time format is HH:MM:SS, and the time zone is represented by the deviation of Greenwich Mean Time (GMT).

echo Date (' R ');
Tue, Feb 2007 14:25:52 +0000
The lowercase R represents the RFC822 date.


The small date () function shows the powerful function and charm of PHP, and then compares the ASP, hehe.

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Advanced Application Tips for PHP date-time functions

PHP's datetime function Date () describes the simple usage of the PHP date-time function, which will introduce more functions to enrich our application.

Checkdate ($month, $date, $year)

If the applied value constitutes a valid date, the function returns to true. For example, for the error date February 31, 2005, this function returns FALSE.

Use this function to check the date and make the date effective before the date is used to calculate or save in the database.
Returns false
echo checkdate (2,30,2005)? "Valid": "Invalid";
Returns True
echo checkdate (4,6,2010)? "Valid": "Invalid";
?>


GETDATE ($ts)

In the absence of an argument, the function returns the current date and time in the form of an array. Each element in the array represents a specific component of a date/time value. You can submit an optional time label argument to the function to get the date/time value that corresponds to the time label.

Apply this function to obtain a series of discrete, easy-to-detach date/time values.

Get date as associative array
$arr = getdate ();
echo "Date is". $arr [' Mday ']. " " . $arr [' Weekday ']. " " . $arr [' Year '];
echo "Time is". $arr [' hours ']. ":" . $arr [' minutes '];
?>


Mktime ($hour, $minute, $second, $month, $day, $year)

This function has the opposite effect of getdate (): It generates a UNIX time label from a series of date and time values (the number of seconds elapsed from GMT January 1, 1970 to now). When no arguments are used, it generates the UNIX time label for the current time.

Use this function to get the UNIX time label for immediate time. This time label is often used in many database and program languages.

Returns timestamp for 13:15:23 7-jun-2006
echo Mktime (13,15,23,6,7,2006);
?>


Date ($format, $ts)

This function formats the UNIX time label as a date string that can be artificially read. It is the most powerful function in the PHP date/Time API and can be used in a series of correction values to convert an integer time label into the desired string format.

This function is applied when the time or date is formatted for display.

Format Current Date
Returns "13-sep-2005 01:16 PM"
echo Date ("D-m-y h:i A", Mktime ());
?>


Strtotime ($STR)

This function converts a human-readable English date/time string into a Unix time label.

Apply this function to convert a non-normalized date/time string into a standard, compatible UNIX time label.

Returns 13-sep-05
echo Date ("D-m-y", Strtotime ("Today"));
Returns 14-sep-05
echo Date ("D-m-y", Strtotime ("Tomorrow"));
Returns 16-sep-05
echo Date ("D-m-y", Strtotime ("Today +3 Days");
?>


Strftime ($format, $ts)

As defined by the previous setlocale () function, this function formats the UNIX time label as a date string for the current environment.

Apply this function to establish a date string that is compatible with the current environment.

Set Locale to France (on Windows)
SetLocale (Lc_time, "Fra_fra");

Format month/day Names
As per locale setting
Returns "Septembre" and "mardi"

Echo strftime ("Month:%B");
echo strftime ("Day:%A");
?>


Microtime ()

As defined by the previous setlocale () function, this function formats the UNIX time label as a date string for the current environment.

Apply this function to establish a date string that is compatible with the current environment.

Get starting value
$start = Microtime ();

Run some code
for ($x =0; $x <1000; $x + +) {
$null = $x * $x;
}

Get ending value
$end = Microtime ();

Calculate time taken for code execution
echo "Elapsed time:". ($end-$start). " SEC ";
?>


Gmmktime ($hour, $minute, $second, $month, $day, $year)

This function generates a UNIX time label from a series of date and time values expressed in GMT time. When no arguments are used, it generates a UNIX time label for the current GMT time.

Use this function to get the UNIX time label for the GMT instant time.

Returns timestamp for 12:25:23 9-jul-2006
echo Gmmktime (12,25,23,7,9,2006);
?>


Gmdate ($format, $ts)

This function formats the UNIX time label as a date string that can be read artificially. This date string is expressed in GMT (non-local time).

This function is applied when the time label is represented in GMT.

Format current date into GMT
Returns "13-sep-2005 08:32 AM"
Echo gmdate ("D-m-y h:i A", Mktime ());
?>


Date_default_timezone_set ($tz), Date_default_timezone_get ()

This function then all date/Time function calls are set and the default time zone is restored.

Note: This function is only valid in PHP 5.1+.

This function is a convenient shortcut for setting the time zone for future operations.


Set TimeZone to UTC
Date_default_timezone_set (' UTC ');
?>

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