相关疑难解决方法(0)

我有以下错误:

警告:preg_replace():第38行的xxx.php中的未知修饰符']'

这是第38行的代码:

<?php echo str_replace("</ul></div>", "", preg_replace("<div[^>]*><ul[^>]*>", "", wp_nav_menu(array('theme_location' => 'nav', 'echo' => false)) )); ?>

有人可以帮我解决这个问题吗？

假设$ body等于

something 
that 
does 
not 
interest 
me 
<!-- start -->
some
html
code
<!-- end -->
something
that
does
not
interest
me

如果我使用

$body=preg_replace("(.*)<!-- start -->(.*)<!-- end -->(.*)","$2",$body);

我获得:

something 
that 
does 
not 
interest 
me 
<!-- start -->
some
html
code
<!-- end -->
something
that
does
not
interest
me

我该如何纠正？