Introduction to PHP eight time functions_PHP tutorial

1. date
usage: date(format,[time]);
If there is no time parameter, the current time is used. The format is a string, in which the following characters have special meanings:
U is replaced by from The number of seconds since a starting time (like January 1, 1970). Y is replaced with a 4-digit year number.
y is replaced with a 2-digit year number.
F is replaced with the full English name of the month. .
M is replaced by the English abbreviation of the month.
m is replaced by the number of months.
z is replaced by the number of days since January 1 of the current year.
d is replaced by the number of days.
l is replaced Replace with the full English name of the day of the week.
D Replace with the English abbreviation of the day of the week.
w Replace with the day of the week (number).
H Replace with the hour (24-hour format).
h Replace into hours (12-hour format).
i is replaced with minutes.
s is replaced with seconds.
A is replaced with "AM" or "PM".
a is replaced with "am" Or "pm".
S is replaced with an ordinal suffix, such as: "st", "nd", "rd", "th".

The function returns the replaced format string.
　
2. getdate(time)
returns a hash table, each subscript is:
"seconds" -- number of seconds
"minutes" -- score
"hours" -- Number of hours
"mday" -- Number of days
"mon" -- Number of months
"year" -- Number of years
"yday" -- Number of days since January 1
"weekday" -- day of the week, full English name
"month" -- month, full English name

3. gmdate
is similar to date, but first converts the time to Greenwich Mean Time .
　
4. mktime
Usage: mktime (hours, minutes, seconds, month, day, year); Returns a time value that can be used in other functions.

5. time
Usage: time(); Returns the number of seconds since midnight on January 1, 1970.

6. microtime
Usage:
microtime(); Returns a string, use The space is divided into two parts. The latter part is equivalent to the return value of time()
, and the former part is the number of microseconds.

7. checkdate
checkdate(month, day, year); returns logical true Or logically false. If:
1. The year is between 1900 and 32767 (including 1900 and 32767);
2. The month is between 1 and 12;
3. The allowed number of days in the month Within the range (taking into account leap years);
returns logical true.

8. set_time_limit
Usage: set_time_limit (seconds);