php 修剪功能不起作用

Question

为什么这总是显示字符串 8，尽管使用了 trim() 函数？它应该从两边删除空格吗？

            $text = " Raveen ";             
            echo "Before trim: ".strlen($text); //prints 8
            trim($text);
            echo "<br>After trim: ".strlen($text); //now prints 6

Answer 1

PHP trim() 函数返回修剪后的字符串，文档 here ，所以代码会是这样的:

$text = " Raveen ";             
echo "Before trim: ".strlen($text); //prints 8
$trimed_text = trim($text);
echo "<br>After trim: ".strlen($trimed_text); //now prints 6