PHP - 将12小时格式时间转换为新时区时出错

Question

我将12小时格式时间从时区转换为新格式时出现错误某时 TimeZone

错误：

Fatal error: Uncaught exception 'Exception' with message 'DateTime::__construct(): Failed to parse time string (00:00:31 AM) at position 9 (A): The timezone could not be found in the database' in C:\xampp\php\udp.php:105
Stack trace:
#0 C:\xampp\php\udp.php(105): DateTime->__construct('00:00:31 AM', Object(DateTimeZone))
#1 {main}  thrown in C:\xampp\php\udp.php on line 105

的 MyCodes： 的

// $gps_time = "9:43:52"; 
$gps_time      = $time_hour.":".$time_min.":".$time_sec;
// $time_received = "01:45:04 2012-07-28"; 
$time_received = date('H:i:s Y-m-d');

$utc = new DateTimeZone("UTC"); 
$moscow = new DateTimeZone("Europe/Moscow"); 

//Instantiate both AM and PM versions of your time 
$gps_time_am = new DateTime("$gps_time AM", $utc); 
$gps_time_pm = new DateTime("$gps_time PM", $utc); 

//Received time 
$time_received = new DateTime($time_received, $moscow); 

//Change timezone to Moscow 
$gps_time_am->setTimezone($moscow); 
$gps_time_pm->setTimezone($moscow); 

//Check the difference in hours. If it's less than 1 hour difference, it's the correct one. 
if ($time_received->diff($gps_time_pm)->h < 1) { 

$correct_time = $gps_time_pm->format("H:i:s Y-m-d");
} 
else { 

$correct_time = $gps_time_am->format("H:i:s Y-m-d");
}

echo $correct_time;

问题： 问题出在哪里!!？ P.S：上面代码是我的udp套接字的一部分，从php cli运行

Answer 1

摘要

简单地说，PHP正在尝试（错误地，根据您的需要）将AM作为时区阅读，AM不是有效时区。

---

详细

10:39:6 AM分为以下几部分

• 10:39:6它识别为timelong24（24小时格式化时间，以秒为单位）
• AM它识别为tz（时区）。

相反，对于10:39:06 AM，它正确地将整个字符串解析为timelong12（12小时格式化时间，秒和上午/下午）。

无聊位

这种奇怪行为的原因在于日期解析逻辑（source）。相关模式是：

<强> timelong24

't'?
[01]?[0-9] | "2"[0-4]              # hour24
[:.]
[0-5]?[0-9]                        # minute
[:.]
[0-5]?[0-9] | "60"                 # second;

<强> timelong12

"0"?[1-9] | "1"[0-2]               # hour12
[:.]
[0-5]?[0-9]                        # minute
[:.]
[0-5][0-9] | "60"                  # secondlz
[ \t]*                             # space?
([AaPp] "."? [Mm] "."?) [\000\t ]  # meridian;

正如您所看到的，要匹配timelong12格式（这是我们真正想要的），的秒部分必须加倍位数。