Replace structure How does this regular write?

Replacement structure How do you write the regular?
In the page:
ISO Preface
Introduction
Switch
ISO Preface
Introduction

$ptext is the content of the page. It's like I'm going to use a reverse reference.

PHP Code

Guidance.

------Solution--------------------

PHP Code

$s = <<< txt page: ISO preface introduction Txt;echo preg_replace (' # title= ". +?/([^]+)" [^>]+> ([^<]+) < #iU ', ' >$2 < ', $s);
------Solution--------------------

  
    
    discuss
 
 
    

 
    
PHP Code
    
$s = <<< TXT
    
In the page:
    
ISO Preface
    


   
  
------Solution--------------------
([^]+) "[^>]+> ([^<]+)

([^]+) This part is a match URL, the general URL does not exist empty
"Is the end of the URL.
[^>]+> is everything that matches not >, that is, there may be other attributes in that tag. Then to the end of the > Header

([^<]+) This is the content of the tag, there is no < (this is the latter part of the label)


Probably this way, I do not know whether I can say that.
------Solution--------------------
Don't really understand this, .... Divert wrote a


  
  

   
   

     PHP Code 
    
$str =<<
  <><\ div="">
   '; $replace = ' $ $ '; Echo preg_replace ("/$REGEXP/", $replace, $STR);
   
------Solution--------------------
   

   
     
     

      
      
    PHP Code
    
      
      

   
     
     
  <\>