PHP教程:strtotime函数用法
strtotime能将任何英文文本的日期时间描述解析为Unix时间戳,我们结合mktime()或date()格式化日期时间获取指定的时间戳,实现所需要的日期时间。
实现功能:获取某个日期的时间戳,或获取某个时间的时间戳。
strtotime 将任何英文文本的日期时间描述解析为Unix时间戳[将系统时间转化成unix时间戳]
一,获取指定日期的unix时间戳 strtotime("2009-1-22") 示例如下:
echo strtotime("2009-1-22") 结果:1232553600
说明:返回2009年1月22日0点0分0秒时间戳
二,获取英文文本日期时间 示例如下:
便于比较,使用date将当时间戳与指定时间戳转换成系统时间
(1)打印明天此时的时间戳strtotime("+1 day")
当前时间:echo date("Y-m-d H:i:s",time()) 结果:2009-01-22 09:40:25
指定时间:echo date("Y-m-d H:i:s",strtotime("+1 day")) 结果:2009-01-23 09:40:25
(2)打印昨天此时的时间戳strtotime("-1 day")
当前时间:echo date("Y-m-d H:i:s",time()) 结果:2009-01-22 09:40:25
指定时间:echo date("Y-m-d H:i:s",strtotime("-1 day")) 结果:2009-01-21 09:40:25
(3)打印下个星期此时的时间戳strtotime("+1 week")
当前时间:echo date("Y-m-d H:i:s",time()) 结果:2009-01-22 09:40:25
指定时间:echo date("Y-m-d H:i:s",strtotime("+1 week")) 结果:2009-01-29 09:40:25
(4)打印上个星期此时的时间戳strtotime("-1 week")
当前时间:echo date("Y-m-d H:i:s",time()) 结果:2009-01-22 09:40:25
指定时间:echo date("Y-m-d H:i:s",strtotime("-1 week")) 结果:2009-01-15 09:40:25
(5)打印指定下星期几的时间戳strtotime("next Thursday")
当前时间:echo date("Y-m-d H:i:s",time()) 结果:2009-01-22 09:40:25
指定时间:echo date("Y-m-d H:i:s",strtotime("next Thursday")) 结果:2009-01-29 00:00:00
(6)打印指定上星期几的时间戳strtotime("last Thursday")
当前时间:echo date("Y-m-d H:i:s",time()) 结果:2009-01-22 09:40:25
指定时间:echo date("Y-m-d H:i:s",strtotime("last Thursday")) 结果:2009-01-15 00:00:00
以上示例可知,strtotime能将任何英文文本的日期时间描述解析为Unix时间戳,我们结合mktime()或date()格式化日期时间获取指定的时间戳,实现所需要的日期时间。

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