php日期和时间基础知识Unix时间戳
<?php/*1.取得当前的Unix时间戳UNIX 时间戳(英文叫做:timestamp)是 PHP 中关于时间与日期的一个很重要的概念,它表示从 1970年1月1日 00:00:00 到当前时间的秒数之和。PHP提供了内置函数 time() 来取得服务器当前时间的时间戳。那么获取当前的UNIX时间戳就很简单了。 */$timer = time();echo $timer;/*2.取得当前的日期php内置了date()函数,来取得当前的日期。函数说明:date(时间戳的格式, 规定时间戳【默认是当前的日期和时间,可选】)返回值:函数日期和时间*/echo date("Y-m-d");echo date("Y-m-d",'1396200000')//1396200000表示时间戳//设置默认的时区date_default_timezone_set('Asia/Shanghai');//输出1396193923对应的日期echo date("Y-m-d",'1396200000')/*取得日期的Unix时间戳UNIX 时间戳(英文叫做:timestamp)是 PHP 中关于时间与日期的一个很重要的概念,它表示从 1970年1月1日 00:00:00 到当前时间的秒数之和。PHP提供了内置函数strtotime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*/echo strtotime('2015-7-27');//1437926400,这个数字表示从1970-1-1到2015-7-27经历了1437926400秒echo strtotime('2015-7-27 05:56:13');//1437947773,这个数字表示从1970-1-1到2015-7-27 05:56:13经历了1437947773秒/*将格式化的日期字符串转换为Unix时间戳strtotime函数预期接受一个包含美国英语日期格式的字符串并且尝试将其解析为Unix时间戳函数说明:strtotime(要解析的时间字符串,计算返回值的时间戳)返回值:成功返回时间戳,否则返回false*/echo strtotime("now");//相当于把现在的日期转化为unix时间戳,这个效果跟echo time()是一样的echo strtotime("+1 seconds");//把现在的时间戳再加上一秒,这个效果跟echo time()+1相同echo strtotime("+1 day");//相当于把现在的时间和日期加上一天,同理echo strtotime("+1 week")//相当于将现在的日期和时间加上一周echo strtotime("+1 week 3 days 7 hours 5 seconds")//相当于将现在的日期和时间加上1周7小时5秒/*格式化格林威治(GMT)标准时间gmdate 函数能格式化一个GMT的日期和时间,返回的是格林威治标准时(GMT)。*/echo date('Y-m-d H:i:s',time())//输出为:2015-07-27 22:40:41echo gmdate('Y-m-d H:i:s',time())//输出为:2015-07-27 16:40:41//返回2014-05-01 12:00:01的格林威治标准时间echo gmdate('Y-m-d H:i:s',strtotime('2014-05-01 12:00:01'))?>
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