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HomeBackend DevelopmentPHP Tutorial指定时间是否为夏令制

如何判断指定时间来获取是否采用美国夏令制

我知道可以写一个函数来判断当前是否为美国夏令制...

但是找咯一下没有说指定时间来判断....


//夏令制判断
function is_dst(){
  $timezone=date('e');  //获取当前使用的时区
  date_default_timezone_set('US/Pacific-New'); //强制设置时区
  $dst=date('I');  //判断是否夏令时
  date_default_timezone_set($timezone);  //还原时区
  return $dst;  //返回结果

}


回复讨论(解决方案)

date 的第二个参数不就是用于指定时间的吗

第二个参数貌似不行...

$lastUpdateint= 13819522810;

echo date("I",lastUpdateint);
返回的结果为0....

不知道我对夏令时的理解是否有误  那只是一种人为的设定吧

时间戳是1970年到某一时间点的秒数   这个某一时间点,在不同的国家 不同的时制下可以有不同的当地时间

但是你怎么有可能得出这个时间秒数是从夏令时的美国得到的呢?


如果不是我理解错误 就是你这个需求是不可能实现的.

 * USA DST
 * From 2:00 AM at the second week of March To  2:00 AM at the first weeek of November
这是美国的夏令时起止时间~

至于所在区域是否使用夏令时需要自己维护一个列表~

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