uninitialized _construct()

[rubing]

I am reading an outstanding php book by Marc Wandschneider called 'Core Web Application Development with  PHP and MySQL'.  However, he does something funny with the _construct() function when delving into the creation of a UserManager class.  Here is his script:

 

<?php

//Database, username, password
require_once('dbconn.inc');
require_once('errors.inc');

class UserManager
{
  function _construct()
     {
         //we don't have initialization just yet
     }

}

 

Now, I thought the purpose of _construct() was stipulate parameters that must be assigned to the object at time of initialization.  What does leaving it blank do?  How is this different than not having a _construct()?

[uniflare]

try naming the constructor function with 2 underscores

 

alternatively name the function exactly the same as the class name

[uniflare]

oops did not read your post.

 

leavingit blank will do nothing, the function will initialize but no code is in the function so it wont do anything.

 

constructors are used to initialize code at the time the class is created eg:

 

<?php

//Database, username, password
require_once('dbconn.inc');
require_once('errors.inc');

class UserManager
{
  function _construct($string)
     {
         echo("Class initialized - $string");     }

}

$usermanagerclass = &New UserManager("hello");
?>

 

would ouput "Class Initialized - Hello"

[BlueSkyIS]

"What does leaving it blank do?  How is this different than not having a _construct()?"

 

as far as i understand, leaving it blank doesn't do anything and it is no different than not having a _construct().

[uniflare]

also, youcan initialize class variables like so:

 

 

<?php
Class classname {
      var $name="mr_blobby";
      var $password=null;
      var $current_user;

      function __construct(){
            echo($this->name." - ".$this->password." - ".$this->current_user);
      }
}

$newclass = &New classname();

?>

would ouput: "mr_blobby -  - "

[rubing]

That's really cool, but why are you placing '&' in front of keyword 'New'

 

&New  ???

[uniflare]

http://forums.whirlpool.net.au/forum-replies-archive.cfm/833742.html

[corbin]

So what's the point of creating it with the &?

 

Why not just pass it with the &?

 

function test(&$class) {}

[uniflare]

the & in front of new has no purpose as i can tell, i just use it as it was used by a book i once read.

i have tried some examples and the & does not seem to affect anything i can see.

 

more information about classes can be found here: http://uk.php.net/manual/en/language.oop5.basic.php

 

 

so yeah, new will work the same as &new, ill keep using the & just incase

[rubing]

I don't know brotha, using that ampersand would make me feel deprecated. I just want to feel 'New' ...<insert bad joke drum sounds>