在页面php之间传递日期并仅显示年份

我一直在页面之间传递用户选择的日期，并调用整个日期而没有任何问题。现在，我只想从 fromdate和 todate中提取年份，下面的代码可以传递日期

I have been passing a user selected date between pages and calling the entire date without any problems. Now I want to ONLY take the year from the "fromdate" and "todate" I have got the code below to pass the date

<?
        $fromdatePost = $_POST["report_date_from"];
        $todatePost = $_POST["report_date_to"];

        $fromdate = $_POST["report_date_from"] .' 00:00:00';
        $fromdate = preg_replace('#(\d{2})/(\d{2})/(\d{4})\s(.*)#', '$3-$2-$1 $4', $fromdate);

        $todate = $_POST["report_date_to"] .' 00:00:00';
        $todate = preg_replace('#(\d{2})/(\d{2})/(\d{4})\s(.*)#', '$3-$2-$1 $4', $todate);  
        ?>

然后我使用以下任意一个显示日期

Then I display the date by using either of the below

'" . $fromdate ."'

或

'" . $fromdate ."'

如何仅显示年份而不是整个日期？！

How do I get it to JUST display the year and not the entire date?!

感谢您的帮助！