PHP and classes

Boby · 03-22-2005, 06:21 AM

Hello!

I have to write some php code and use classes. One class is for formating text and one for output. These are some simplyfied examples:

PHP Code:



<?php 
class Operations 
{ 
   function format_result($string) 
   { 
      // Remove HTML and PHP tags 
      $string = strip_tags( $string ); 
      // Remove "\r\n", "\r" and "\n" with a space 
      $string = str_replace( "\r\n" , " ", $string ); // Windows 
      $string = str_replace( "\r"   , " ", $string ); // Mac OS 
      $string = str_replace( "\n" , " ", $string ); // Unix 
      // Remove tabs "\t" 
      $string = str_replace( "\t" , " ", $string ); 
      // Remove multiple spaces 
      $string = preg_replace( "/\s{2,}/", " ", $string ); 
 
      return $string; 
   } 
 
   function highlight_keyword($string, $keyword) 
   { 
     $string = preg_replace("#(".$keyword.")#si", '<span class="highlight">\1</span>', $string); 
 
     return $string; 
   } 
} //end class 
 
class output 
{ 
   var $string = ""; 
   var $keyword = ""; 
   var $job; 
 
   function format() 
   { 
      $this->job = new Operations; 
   } 
 
   function import($string, $keyword) 
   { 
      $this->string = $string; 
      $this->keyword = $keyword; 
   } 
 
   function make_output() 
   { 
      echo "<div>".$this->job->format_result($string)."<br />".$this->job->highlight_keyword($string, $keyword)."</div>"; 
   } 
} //end class 
 
$text = "  This is a random    text for this     thread.  Text is now ready"; 
$word = "text"; 
 
$class = new output(); 
$class->import($text, $word); 
$class->format(); 
$class->make_output() 
?>

The problem is it doesn't work because it won't use the class "Operations" in the class "output". How do I use the first class in the second one? I've read some documentation of PHP but I couldn't get it work. It would be very nice to have some code examples from you.

Thank you!
Regards, Boby!

keefaz · 03-22-2005, 06:30 AM

A way to fix it :

PHP Code:



function make_output() 
   { 
      $job = $this->job; 
      echo "<div>".$job->format_result($string)."<br />".$job->highlight_keyword($string, $keyword)."</div>"; 
   }

Another way :

PHP Code:



class output extends Operations { 
... 
function make_output() 
   { 
      echo "<div>".$this->format_result($string)."<br />".$this->highlight_keyword($string, $keyword)."</div>"; 
   }

another way :

PHP Code:



function make_output() 
   { 
      echo "<div>".Operations::format_result($string)."<br />".Operations::highlight_keyword($string, $keyword)."</div>"; 
   }

Boby · 03-22-2005, 10:29 AM

Thank you very much keefaz!
You are great!

I am using now your last choice:

PHP Code:



function make_output() 
   { 
      echo "<div>".Operations::format_result($string)."<br />".Operations::highlight_keyword($string, $keyword)."</div>"; 
   }

This looks the best for me!

Thank you again!
Cheers, Boby!

keefaz · 03-22-2005, 11:14 AM

The third choice is possible here because Operations is a static class (no use of $this)
If you use it, you could remove

PHP Code:



function format() 
   { 
      $this->job = new Operations; 
   }

...as it is not longer needed

Boby · 03-23-2005, 01:49 AM

So if I use $this->function or $this->variable in the first class I won't be able to use the above example choosed by me and I have to use the one with "class foo extends bar"?

If not when do I use this example or the other example?

Thank you!
Boby

keefaz · 03-23-2005, 05:15 AM

Yes, you can't use $this on a static class
But you don't need absolutely do an extends, you can follow the
first example and keep your format() function that initialize
Operations class