去除字符串的最后一行空行

<?php
$s = 'Foo
Bar
Baz
';
$s_replaced = preg_replace('//', '', $s);
$s_replaced = rtrim($s_replaced);
$out = '<textarea cols=30 rows=10>'.$s_replaced.'</textarea>';
echo $out;
?>

使用rtrim() 。

使用：

$s_replaced = preg_replace("/".PHP_EOL."$/", '', $s);

试试这个：

查找方式：

(?s)'s+$

替换为：

none

解释：

<!--
(?s)'s+$
Options: case insensitive; ^ and $ match at line breaks
Match the remainder of the regex with the options: dot matches newline (s) «(?s)»
Match a single character that is a “whitespace character” (spaces, tabs, and line breaks) «'s+»
   Between one and unlimited times, as many times as possible, giving back as needed (greedy) «+»
Assert position at the end of a line (at the end of the string or before a line break character) «$»
-->