PHP code to display date and time_PHP tutorial

PHP’s time display code is much more powerful than ASP, and it is simpler to call.
1. Year-month-day
echo date('Y-m-j');
2012-02-6
echo date('y-n-j');
07-2-6
An uppercase Y represents a four-digit year, while a lowercase y represents a two-digit year;
Lowercase m represents the number of the month (with a leading), while lowercase n represents the number of the month without the leading.

echo date('Y-M-j');
2012-Feb-6
echo date('Y-m-d');
2012-02-06
Uppercase M represents the 3 abbreviated characters of the month, while lowercase m represents the number of the month (with leading 0);
There is no uppercase J, only lowercase j represents the day of the month, without the leading o; if a leading month is required, use a lowercase d.
echo date('Y-M-j');
2012-Feb-6
echo date('Y-F-jS');
2012-February-6th
Capital M represents the 3 abbreviated characters of the month, while capital F represents the full English letter of the month. (no lowercase f)
Capital S represents the suffix of the date, such as "st", "nd", "rd" and "th", depending on the date number.

Summary:
You can use uppercase Y or lowercase y to indicate the year;
Months can be represented by uppercase F, uppercase M, lowercase m and lowercase n (two ways to represent characters and numbers respectively);
Lowercase d and lowercase j can be used to represent the day, and uppercase S represents the suffix of the date.

2. Hour:minute:second
By default, PHP interprets the displayed time as "Greenwich Mean Time", which is 8 hours different from our local time.
echo date('g:i:s a');
5:56:57 am
echo date('h:i:s A');
05:56:57 AM
A lowercase g indicates a 12-hour clock without leading 0s, while a lowercase h indicates a 12-hour clock with leading 0s.
When using the 12-hour clock, it is necessary to indicate morning and afternoon. Lowercase a represents lowercase "am" and "pm", and uppercase A represents uppercase "AM" and "PM".

echo date('G:i:s');
14:02:26
Capital G represents the hour in 24-hour format, but without leading; use capital H to represent hour in 24-hour format with leading
Summary:
The letter g represents the hour without leading, and the letter h represents the hour with leading;
Lowercase g and h represent the 12-hour format, while uppercase G and H represent the 24-hour format.

3. Leap year, week, day
echo date('L');
Whether this year is a leap year: 0

echo date('l');
Today is: Tuesday
echo date('D');
Today is: Tue
Capital L indicates whether this year is a leap year, Boolean value, returns 1 if true, otherwise 0;
The lowercase l represents the full English word for the day of the week (Tuesday);
Instead, use a capital D to represent the 3-character abbreviation of the day of the week (Tue).

echo date('w');
Today’s week: 2
echo date('W');
This week is week 06 of the year
The lowercase w represents the day of the week, and the numeric form represents
Capital W represents the number of weeks in the year

echo date('t');
This month is 28 days
echo date('z');
Today is the 36th day of the year
Lowercase t represents the number of days in the current month
Lowercase z indicates what day of the year today is

4. Others
echo date('T');
UTC
A capital T represents the server’s time locale

echo date('I');
0
Capital I means to determine whether the current daylight saving time is, if true, return 1, otherwise 0

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

echo date('c');
2012-02-06T14:24:43+00:00
Lowercase c represents an ISO8601 date, the date format is YYYY-MM-DD, the letter T is used to separate the date and time, the time format is HH:MM:SS, and the time zone is represented by the offset from Greenwich Mean Time (GMT).

echo date('r');
Tue, 06 Feb 2007 14:25:52 +0000
Lowercase r indicates RFC822 date