Puzzled about PHP Class Scope and includes

firemankurt

I am thinking about building a modular validation class where different files are included depending on the data being checked.

While getting ready to start building this I came across some stuff that works but I don't understand why.

Why does this allow me to "require" the same file multiple times without throwing an error?

How does the server load, execute, and ???unload??? files in function MMVtest()?
Does it load it all and then execute or load during execution and unload when it is done with MMVtest()? I really don't understand the scope of classes in this case.

Here are the test files all in one directory:
Test.php ( The main file that will have data I want to check - Open This page to execute the code.)

<?php
include ('Mod.php');

$MyText = new MMVobj();
$MyText2 = new MMVobj();
$MyText3 = new MMVobj();

echo "<p>".$MyText->MESS."-".$MyText->ERROR."</p>";
echo "<p>".$MyText2->MESS."-".$MyText2->ERROR."</p>";
echo "<p>".$MyText3->MESS."-".$MyText3->ERROR."</p><hr/>";

echo "<p>MyText1- Calling Test  'simple'</p>";
echo "<p>MyText2- Calling Test  'simple2'</p>";
$MyText->MMVtest('simple',"MyText");
$MyText2->MMVtest('simple2',"MyText2");

echo "<p>".$MyText->MESS."-".$MyText->ERROR."</p>";
echo "<p>".$MyText2->MESS."-".$MyText2->ERROR."</p>";
echo "<p>".$MyText3->MESS."-".$MyText3->ERROR."</p><hr/>";

echo "<p>MyText1- Calling Test  'simple'</p>";
echo "<p>MyText2- Calling Test  'simple2'</p>";
echo "<p>MyText3- Calling Test  'simple3'</p>";
$MyText->MMVtest('simple',"MyText");
$MyText2->MMVtest('simple2',"MyText2");
$MyText3->MMVtest('simple3',"MyText3");

echo "<p>".$MyText->MESS."-".$MyText->ERROR."</p>";
echo "<p>".$MyText2->MESS."-".$MyText2->ERROR."</p>";
echo "<p>".$MyText3->MESS."-".$MyText3->ERROR."</p><hr/>";

echo "<p>MyText1- Calling Test  'simple2'</p>";
echo "<p>MyText2- Calling Test  'simple3'</p>";
$MyText->MMVtest('simple2',"MyText");
$MyText2->MMVtest('simple3',"MyText2");

echo "<p>".$MyText->MESS."-".$MyText->ERROR."</p>";
echo "<p>".$MyText2->MESS."-".$MyText2->ERROR."</p>";
echo "<p>".$MyText3->MESS."-".$MyText3->ERROR."</p><hr/>";
?>

Mod.php ( The Main Class File that constructs the validators)

<?php
class MMVobj
{
	var $ERROR	=	""; // Short  Error Description
	var $MESS	=	""; // Message to present to user

function MMVobj ()
{
	return;
}

    function MMVtest ($TestType, $data)
{
	require $TestType.'.php';
}

}
?>

3 Files all the same simple.php, simple2.php, simple3.php
(This will be all different later to do different checks)

<?php
$this->MESS = $data;
$this->ERROR = $TestType;

?>

Thanks all....:queasy: 😕

sheephat

$TestType where is this set?

Shrike

There is no reason at all why you can't call require() as many times as you like. All it does is take the content of the required file and run it within the current context. So if a file contained <?='hello'?> and you require()'d it 3 times, you'd just get 'hello' 3 times. However if the file contained a function and you called require on it 3 times then you'd get a fatal error telling you that you can't redefine that function. The functions require_once and include_once are there to prevent this problem.

Shrike

With regard to designing a modular validation system, using require to change the behaviour of a class would be a bad code smell.

A common approach to this problem is to have a base class to define an API, and subclasses defining the actual validation. This topic has cropped up several times recently so you'd do well to search the boards.

firemankurt

Sheephat,

$TestType where is this set?

it is set by calling:

$MyText->MMVtest('simple',"MyText"); / <- from Test.php

which looks like:

        function MMVtest ($TestType, $data) / <- from Mod.php
    {
        require $TestType.'.php';  / <- This is used as a file name and text for my expirment.
    }

Shrike,

Thanks for redirecting me to what I should have been able to see be was not.
So do you guys think this is a bad idea (To essentially change that content of a function on the fly for each object) or did I do something right this time🙂 .

p.s. I really am sorry for the cross post earlier...