Php create class method dynamically

Question

Instead of "creating" functions, you can use the magic method __call(), so that when you call a "non-existent" function, you can handle it and do the right action.

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7.12. Creating a Class Dynamically
Code to call a method dynamically
Example to call other class method dynamically
How to call method dynamically in PHP?
How to create function dynamically in PHP?
How do you call a class method in PHP?

Something like this:

class MyClass{
    private $array = array('one', 'two', 'three');

    function __call($func, $params){
        if(in_array($func, $this->array)){
            return 'Test'.$func;
        }
    }
}

Then you can call:

$a = new MyClass;
$a->one(); // Testone
$a->four(); // null

DEMO: http://ideone.com/73mSh

EDIT: If you are using PHP 5.3+, you actually can do what you are trying to do in your question!

class MyClass{
    private $array = array('one', 'two', 'three');

    function __construct(){
        foreach ($this->array as $item) {
            $this->$item = function() use($item){
                return 'Test'.$item;
            };
        }
    }
}

This does work, except that you can't call $a->one() directly, you need to save it as a variable.

$a = new MyClass;
$x = $a->one;
$x() // Testone

DEMO: http://codepad.viper-7.com/ayGsTu

7.12. Creating a Class Dynamically

Problem

You want to create a class, but you don’t know everything about it until your code is executed.

Solution

Use eval( ) with interpolated variables:

eval("class van extends $parent_class {
    function van() {
        \$this->$parent_class();
    }
};");

$mystery_machine = new van;

Discussion

While it’s okay in PHP to use variable names to call functions or create objects, it’s not okay to define functions and classes in a similar manner:

$van( );                     // okay
$van = new $parent_class    // okay
function $van( ) {};         // bad
class $parent_class {};     // bad

Trying to do either of the last two examples results in a parser error because PHP expects a string, and you supplied a variable.

So, if you want to make a class named $van and you don’t know beforehand what’s going to be stored in $van, you need to employ eval( ) to do your dirty work:

eval("class $van {};");

There is a performance hit whenever you call eval( ), so high traffic sites should try to restructure their code to avoid this technique when possible. Also, if you’re defining your class based on input from users, be sure to escape any potentially dangerous characters.

A simple definition for methods is: Methods are functions encapsulated within a class. Now lets explain how to dynamically call methods.

Sometimes we need to call different methods as per our requirement and conditions. To do so, we can call any method dynamically.

To call a method dynamically means that we can assign method name to any variable and call the method using that variable, either in switch case of if else block or anywhere depending on our requirement. Below is the snippet and code explanation which demonstrate how to call a method dynamically.

Code to call a method dynamically

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<?php

classDynamicCalling{

publicfunctioncaller($to_call){

echo'<h4>Calling "'. $to_call.'" method</h4>';

if(is_callable([$this,$to_call])){

$this->$to_call();

}else{

echo'<h3>Unable to call "'.$to_call.'" method: method missing</h3>';

}

publicfunctionmethodOne(){

echo'<h3>This is methodOne.</h3>';

}

private functionmethodTwo(){

echo'<h3>This is methodTwo.</h3>';

}

echo'<center>';

$dcObject= newDynamicCalling();

$dcObject->caller('methodOne');

echo'<hr/>';

$dcObject->caller('methodAny');

echo'<hr/>';

$dcObject->caller('methodTwo');

?>

Code explanation:

Above is a class DynamicCalling which has three methods: caller(), methodOne(), methodTwo().

Purpose of the caller() method is to call other methods by passing their names as argument $to_call. If the method of the name same as the value of $to_call is callable, i.e. available and can be called, then it is called. This validity is checked by is_callable() function of core PHP in which passed $this as object of same class for method reference and $to_call as method name to check valid method of class DynamicCalling.

If you need to call method of any other class, simply replace the $this with object of that class and pass the method name.

Example to call other class method dynamically

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<?php

classDynamicCalling{

publicfunctioncaller($to_call){

echo'<h4>Calling "'. $to_call.'" method</h4>';

if(is_callable([$this,$to_call])){

$this->$to_call();

}else{

echo'<h3>Calling method in ThirdParty class.</h3>';

$tpObject= newThirdParty();

if(is_callable([$tpObject,$to_call])){

$tpObject->$to_call();

}else{

echo'<h3>"'.$to_call.'" method not found in ThirdParty class</h3>';

}

publicfunctionmethodOne(){

echo '<h3>This is methodOne.</h3>';

}

privatefunctionmethodTwo(){

echo'<h3>This is methodTwo.</h3>';

}

classThirdParty{

publicfunctionmethodAny(){

echo'<h3>This is methodAny of ThirdParty class.</h3>';

}

echo'<center>';

$dcObject=newDynamicCalling();

$dcObject->caller('methodOne');

echo'<hr/>';

$dcObject->caller('methodAny');

echo'<hr/>';

$dcObject->caller('methodTwo');

?>

How to call method dynamically in PHP?

To call a method dynamically means that we can assign method name to any variable and call the method using that variable, either in switch case of if else block or anywhere depending on our requirement.

How to create function dynamically in PHP?

If you're using PHP 5.3 you could use an anonymous function. <? php $functionName = "doStuff"; $$functionName = function($args) { // Do stuff }; $args = array(); $doStuff($args); ?> Technically, this doesn't define a function, but a closure.