Dynamically generate classes at runtime in php?

Question

Here\'s what I want to do:

$clsName = substr(md5(rand()),0,10); //generate a random name
$cls = new $clsName(); //create a new instance

function __autoload(         


        

Answer 1

This is almost certainly a bad idea.

I think your time would be better spent creating a script that would create your class definitions for you, and not trying to do it at runtime.

Something with a command-line signature like:

./generate_classes_from_db <host> <database> [tables] [output dir]

Answer 2

Please read everyone else answers on how this is truly a very very bad idea.

Once you understand that, here is a small demo on how you could, but should not, do this.

---

<?php
$clname = "TestClass";

eval("class $clname{}; \$cls = new $clname();");

var_dump($cls);

Answer 3

I think using eval() it's not a reliable solution, especially if your script or software will be distributed to different clients. Shared hosting providers always disable eval() function.

I'm thinking of a better aproach like this :

<?php 

 function __autoload( $class ) {
      require 'classes/'.$class.'.php';

}

$class = 'App';
$code = "<?php class $class {
    public function run() {
        echo '$class<br>';  
    }
    ".'
    public function __call($name,$args) {
        $args=implode(",",$args);
        echo "$name ($args)<br>";
    }
}';

file_put_contents('classes/App.php' ,$code);

$a = new $class();
$a->run();

After finishing executing the code, you can delete the file if you want, I tested it and it works perfectly.

Answer 4

function __autoload($class)  {
    $code = "class $class {`
        public function run() {
            echo '$class<br>';  
        }
        ".'
        public function __call($name,$args) {
            $args=implode(",",$args);
            echo "$name ($args)<br>";
        }
    }';

    eval($code);
}

$app=new Klasse();
$app->run();
$app->HelloWorld();

This might help to create a class at runtime. It also creates a methor run and a catchall method for unknown methods But better create Objects at runtime, not classes.