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HomeBackend DevelopmentPHP TutorialPHP时间和日期函数详解_php实例

PHP中所有函数都是UNIX纪元的,即从1970年1月1日开始的。

日期是从这个时候开始的秒数。

当一个函数调用从这时候计的秒数时,就把它当作(timestamp)时间戳。

本地时间函数

1. string date(string format,inieger timestamp)

该函数返回一个表示时间的字符串,是由string format 控制的。
如:

<&#63;
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.
&#63;>

也许你会问,怎麽没有timestamp呢?若timestamp为空时,或不写时,表示使用当前时间一刻timestamp.
表示年份的控制符: Y---四位的年份 y---两位的年份
表示月份的控制符: m---从1-12的月份 F---英文月份名 M---简写的月份名
表示日号的控制符: d---前面有0的月份中日期 j--前面没有0的日号
表示星期的控制符: l--英文星期 D--简写的星期
表示小时的控制符: h--从1到12小时 H---从0到23的小时
表示上下午的控制符 a ---am或pm A---AM或PM
表示分钟的控制符: i---取值00-59
表示一年中第多少天: z--一年中的第多少天

2. array getdate(integer timestamp)

该函数返回一个矩阵.
如:

<&#63;
$current_date=getdate();
print($current_date("hours"));
print($current_date("minutes");
print($current_date("seconds");
&#63;>

说明:
元素 描述
hours 24小时格式的小时
mday 月份中日期
minutes 分钟
mon 数字形式的月份
month 月份全称
seconds 秒数
wday 从0到6的数字形式的星期几
weekday 星期几的名称
year 年份
0 时间戳即从1970年1月1日到现在的秒数
yday 一年中数字形式的日期

3. boolean checkdate(integer month,integer day,integer year)
该函数检查日期是否合法.如:

<&#63;
if(checkdate(2,29,1980))
print("日期合法!n");
&#63;>

4. integer time()

该函数获得当前时间戳.如:

<&#63;
print(time());//输出一大串整数
&#63;>

5. integer mktime(integer hour,integer minutes,integer seconds,integer month, integer day,integer year)

该函数返回给出日期的时间戳,即从1970年1月1日到现在的秒数.
如某参数超出范围,该函数也可以解释它,如13月即为第二年的一月.
如:

<&#63;
$currenthour=date("H");
print("50个小时后为:");
print(date("h:i A l F dS,Y",mktime($currenthour+50)));
print("<br>n");
&#63;>

6. string microtime()

该函数返回一个字符串,由当前时间的毫秒数+空格+从1970年开始的秒数

<&#63;
print("start:microtime()<br>n");
for($index=0;$index<1000;$index++)
print("good!");
print("stop:microtime()<br>n");
&#63;>

还有,各林威治标准时间函数

以上所述就是本文的全部内容了,希望大家能够喜欢。

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