// Set the default timezone to use. Available since PHP 5.1
date_default_timezone_set('UTC');


// Prints something like: Monday
echo date("l");

// Prints something like: Monday 8th of August 2016 03:12:46 PM
echo date('l jS \of F Y h:i:s A');

// Prints: July 1, 2016 is on a Saturday
echo "July 1, 2016 is on a " . date("l", mktime(0, 0, 0, 7, 1, 2016));

/* Use the constants in the format parameter */
// Prints something like: Wed, 25 Sep 2013 15:28:57 -0700
echo date(DATE_RFC2822);

// Prints something like: 2016-07-01T00:00:00+00:00
echo date(DATE_ATOM, mktime(0, 0, 0, 7, 1, 2000));

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。

// Set the default timezone to use. Available since PHP 5.1
date_default_timezone_set('UTC');


// Prints something like: Monday
echo date("l");

// Prints something like: Monday 8th of August 2016 03:12:46 PM
echo date('l jS \of F Y h:i:s A');

// Prints: July 1, 2016 is on a Saturday
echo "July 1, 2016 is on a " . date("l", mktime(0, 0, 0, 7, 1, 2016));

/* Use the constants in the format parameter */
// Prints something like: Wed, 25 Sep 2013 15:28:57 -0700
echo date(DATE_RFC2822);

// Prints something like: 2016-07-01T00:00:00+00:00
echo date(DATE_ATOM, mktime(0, 0, 0, 7, 1, 2000));

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");
?>

PHP的time()返回当前Unix时间戳。这样，您就可以使用date()函数将其格式化为您需要的格式。

$date = date('Format String', time());

正如Paolo在评论中提到的，第二个论点是多余的。下面的代码段相当于上面的代码段:

$date = date('Format String');

设置时区:

date_default_timezone_set('Asia/Calcutta');

然后调用日期函数

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