The diversification and similar functions of PHP functions are really a major feature. The same application can be implemented with multiple functions, which is probably a drawback of open source; through the systematic study of PHP time functions, I fully understand the time stamp and The concept of time zone (this is really important), friends in need can refer to it.
All functions in PHP are from the UNIX era, that is, starting from January 1, 1970.
The date is the number of seconds since this time.
When a function calls the number of seconds since this time, treat it as a (timestamp) timestamp.
Local time function
1. string date(string format,inieger timestamp)
This function returns a string representing the time, which is String format controlled.
For example:
<? print(date("Y年 m月d日");//输出当前,年月日. print(date("Y年 m月d日",60*60*24*365*10);//输出1980年1月1日. ?>
Maybe you will ask, why is there no timestamp? If timestamp is empty, or does not write, it means that the current time timestamp is used.
The control character indicating the year: Y ---four-digit year y---two-digit year
represents the control character of the month: m---month from 1-12 F---English month name M---abbreviated month name
The control character indicating the day number: d---The day in the month with 0 in front j--The day number without 0 in front
The control character indicating the week: l--English week D--Abbreviated week
represents the hour control character: h--hours from 1 to 12 H---hours from 0 to 23
represents the control character for morning and afternoon a ---am or pm A---AM or PM
represents the minute control character: i---value 00-59
represents the number of days in a year: z--the number of days in a year
2. array getdate(integer timestamp)
This function returns a matrix.
For example:
<? $current_date=getdate(); print($current_date("hours")); print($current_date("minutes"); print($current_date("seconds"); ?>
Description:
Element description
hours Hours in 24-hour format
mday Date in month
minutes Minutes
mon Month in numeric form
month Full name of month
seconds Number of seconds
wday Day of the week in numeric form from 0 to 6
weekday Day of the week The name of (integer month, integer day, integer year)
This function checks whether the date is legal. For example:
<? if(checkdate(2,29,1980)) print("日期合法!n"); ?>
4. integer time()
This function obtains Current timestamp. For example:
<? print(time());//输出一大串整数 ?>
5. integer mktime(integer hour,integer minutes,integer seconds,integer month, integer day,integer year)
This function Returns the timestamp of the given date, that is, the number of seconds from January 1, 1970 to the present.
If a parameter is out of range, this function can also interpret it, for example, 13th is January of the next year. Such as: <?
$currenthour=date("H");
print("50个小时后为:");
print(date("h:i A l F dS,Y",mktime($currenthour+50)));
print("<br>n");
?>
This function returns a string consisting of the milliseconds of the current time and the seconds starting from 1970. Number
<? print("start:microtime()<br>n"); for($index=0;$index<1000;$index++) print("good!"); print("stop:microtime()<br>n"); ?>
Also, various Linwich Mean Time functions
Summary: The above is the entire content of this article, I hope it can be helpful to everyone’s study .
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