非常简单 echo $date = date('Y-m-d H:i:s');

日期格式也取决于:

echo date("d/m/Y H:i:sa"); // 13/04/2017 19:38:15pm

我们可以使用date函数设置默认时区:

<?php
    date_default_timezone_set("Asia/Kolkata");
    echo "Today is " . date("Y/m/d") . "<br>";
    echo "Today is " . date("Y.m.d") . "<br>";
    echo "Today is " . date("Y-m-d") . "<br>";
    echo "Today is " . date("l");
    echo "The time is " . date("h:i:sa");
?>

Linux服务器时间与PHP time()时区差异如下:

<?php
    putenv("TZ=Asia/Kabul");
    $t = time();
    echo date('d/m/Y H:i:sa', $t);
?>

// Simply:
$date = date('Y-m-d H:i:s');

// Or:
$date = date('Y/m/d H:i:s');

// This would return the date in the following formats respectively:
$date = '2012-03-06 17:33:07';
// Or
$date = '2012/03/06 17:33:07';

/** 
 * This time is based on the default server time zone.
 * If you want the date in a different time zone,
 * say if you come from Nairobi, Kenya like I do, you can set
 * the time zone to Nairobi as shown below.
 */

date_default_timezone_set('Africa/Nairobi');

// Then call the date functions
$date = date('Y-m-d H:i:s');
// Or
$date = date('Y/m/d H:i:s');

// date_default_timezone_set() function is however
// supported by PHP version 5.1.0 or above.

有关时区参考，请参见支持的时区列表。

您可以使用$_SERVER['REQUEST_TIME']变量(自PHP 5.1.0起可用)或time()函数来获取当前的Unix时间戳。