只写:

date("Y") // A full numeric representation of a year, 4 digits
          // Examples: 1999 or 2003

Or:

date("y"); // A two digit representation of a year     Examples: 99 or 03

然后“echo”这个值…

$year = date("Y", strtotime($yourDateVar));

在date函数的第二个参数中可以得到更多的值 Strtotime返回参数传递的时间戳

// This work when you get time as string
echo date('Y', strtotime("now"));

// Get next years
echo date('Y', strtotime("+1 years"));

// 
echo strftime("%Y", strtotime("now"));

使用datetime类

echo (new DateTime)->format('Y');

<?php echo date("Y"); ?>

顺便说一句……网站版权展示有几种合适的方式。有些人倾向于让事情变得多余，例如:版权©具有相同的含义。重要的版权部分包括:

**Symbol, Year, Author/Owner and Rights statement.** 

使用PHP + HTML:

<p id='copyright'>&copy; <?php echo date("Y"); ?> Company Name All Rights Reserved</p>

or

<p id='copyright'>&copy; <?php echo "2010-".date("Y"); ?> Company Name All Rights Reserved</p

print date('Y');

有关更多信息，请查看date()函数文档:https://secure.php.net/manual/en/function.date.php