PHP regular unknown modifier error Resolution _php tips

The following are:

$a = ' 2<span><nobr>tóng<span class= ' h ' >dòng</span></nobr><br> dong </span>3 ' ; echo preg_replace ('/<span class= "h" >[^<]*?</span>/', ', $a);

Will prompt:

Warning:preg_replace (): Unknown modifier ' P ' in E:\phpLearn\test.php on line 12

The reason is:

In regular mode, use/do delimiters, but also include/in regular, so this error occurs, PHP mistakenly when the next </span> in the trailing slash is the end of the delimiter.

Solution:

1, plus an escape character:

echo preg_replace ('/<span class= "h" >[^<]*?<\/span>/', ', $a);

2, change other delimiters: such as

Echo preg_replace (' {<span class= "H" >[^<]*?</span>} ', ', $a);