在PHP中设置时区偏移量

Question

我正在编写一个API，它将从传感器中检索读数并返回时间和值列表，偏移量使用Javascript的new Date（）。（见下文的原因）

我已经能够获取时间加法/减法的工作做得不够好，使用$date->sub(DateInterval::createFromDateString($offset . " minutes"))，但返回的时间和日期的偏移量+00：（而不是00如2016-02-26T13:32:28+00:00澳大利亚2016-02-26T13:32:28+11:00）。

这会导致问题的东西，如卵石，或AngularJS，适用于我自己的顶自己的偏移，看到偏移后+00：00

我怎样才能正确地设置一个呼叫时偏移$date->format("c")？我应该自己编译日期（例如$date->format("Y-m-d\TH:i:s" . $plusOrMinus . $myoffset->format("h:i"))）还是有更好的方法来做到这一点？

编辑：由于平台限制（例如Pebble smartwatch），我不能或不想使用时区名称，因为在我的手表应用程序中实现时区菜单会破坏UX或驱动文件大小如果我添加一个偏移到时区表/库

Answer 1

我得到这个排序在最后。从PHP manual信息的该位放倒我送行：

在$时区参数和当前时区被忽略时，$时间参数要么是一个UNIX时间戳（如@ 946684800），或者指定一个时区（如2010- 01-28T15：00：00 + 02：00）。

所以我最终的解决方案是扩展DateTime类并覆盖__construct()方法。我的修改后的类如下：

<?php 

    class timezone extends DateTime { 

    // Override our __construct method 
    function __construct($date = "now", $offset = null) { 
     // If we've not specified an offset 
     if(is_null($offset)) { 
      // Assume UTC 
      $offsetFormat = "+00:00"; 
      $offset = 0; 
     // Otherwise.. 
     } else { 
     // Create a new DateTime, and get the difference between that, and another new DateTime that has $offset minutes subtracted from it. Format the results as something like +11:00 or -03:00 
     $offsetFormat = (new DateTime($date, new DateTimeZone("UTC")))->diff((new DateTime($date, new DateTimeZone("UTC")))->sub(DateInterval::createFromDateString($offset . " minutes")))->format("%R%H:%I"); 
     } 

     // Next, we get the offset from our $date. If this offset (divided by 60, as we're working in minutes, not in seconds) does NOT equal our offset 
     if((new DateTime($date))->getOffset()/60 !== $offset) { 
     // Overwrite $date, and set it to a new DateTime with $offset minutes subtracted from it 
     $date = (new DateTime($date, new DateTimeZone("UTC")))->sub(DateInterval::createFromDateString($offset . " minutes")); 
     // If $date's offset equals $offset 
     } else { 
     // An offset has already been applied (we know this because all our pre-offset dates will be in UTC), and we don't need to do it again 
     $date = (new DateTime($date)); 
     } 

     // Finally, hand this back to the original DateTime class. This format works out to be something like: 2016-03-10T23:16:37+11:00 
     parent::__construct($date->format("Y-m-d\TH:i:s") . $offsetFormat, null); 
    } 

    } 


    echo (new timezone())->format("c") . "<br />"; // Will output something like 2016-03-10T12:17:44+00:00 
    echo (new timezone(null, -660))->format("c") . "<br />"; // Will output something like 2016-03-10T23:17:44+11:00 
    echo (new timezone("midnight", -660))->format("c") . "<br />"; // Will output 2016-03-10T11:00:00+11:00 
    echo (new timezone("midnight"))->format("c") . "<br />"; // Will output 2016-03-10T00:00:00+00:00 
    echo (new timezone("2016-01-01T00:00+00:00", -660))->format("c") . "<br />"; // Will output 2016-01-01T11:00:00+11:00 
    echo (new timezone("2016-01-01T00:00+11:00", -660))->format("c") . "<br />"; // Will output 2016-01-01T11:00:00+11:00. Note that the offset isn't applied twice! 

?> 

编辑：这是现在我已经开源的库。 Check it out over on GitHub

Answer 2

是这样吗？

$date = new DateTime('now', new DateTimeZone('Australia/Adelaide')); 
var_dump($date); 
var_dump($date->format('c')); 

输出

object(DateTime)[2] 
    public 'date' => string '2016-02-26 13:35:48.000000' (length=26) 
    public 'timezone_type' => int 3 
    public 'timezone' => string 'Australia/Adelaide' (length=18) 
string '2016-02-26T13:35:48+10:30' (length=25)