php create instance of another class

Question

I'm totally new to php(migrating from java). There are two classes

First.php

class First {

    public function method(){
        #how to call second object like java
        #$obj=new Second();
    }
}

Second.php

class Second{
    public function method_second(){
        echo 'second method';
    }
}

Can't we create object of Second.php in First.php

Yes, you can, as long as you have `include`d (or `require`d) Second.php or defined an autoloader. — elixenide, May 12 '15 at 18:58
@EdCottrell: I'm not a big time OOP guy, but I thought that was "bad"? — AbraCadaver, May 12 '15 at 19:01
@AbraCadaver not all dependencies of this type are avoidable. Think, for example, of a factory class. It obviously has to instantiate other classes to do its job. — elixenide, May 12 '15 at 19:05
@Exbury Like I said, you have to `include`, `require`, or autoload your second class; you can't just refer to it without telling PHP where the class is defined. — elixenide, May 12 '15 at 19:07

Marin Bînzari · Accepted Answer · 2015-05-12T19:05:01.233

3

You should include the Second.php file in the First.php to have access to the Second class:

<?php
include "Second.php";
class First {
    public function method(){
        #how to call second object like java
        $obj=new Second();
    }
}

Also you can use an autoloader ( not the best example :) ):

<?php
function __autoload($class_name) {
    include $class_name . '.php';
}

class First {
    public function method(){
        #how to call second object like java
        $obj=new Second();
    }
}
?>

More info about autoloaders can be found on php.net: http://php.net/manual/en/language.oop5.autoload.php

edited May 12 '15 at 19:05

answered May 12 '15 at 18:59

Marin Bînzari

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can we use without register autoload – Bruce May 12 '15 at 19:11
@Exbury, No, you are forced to choose between `include "Second.php";`, `require "Second.php";` or the `autoloader`. The PHP should know where the class is defined and these are methods you should use to tell where the class is located. – Marin Bînzari May 12 '15 at 19:12
Another question i have if add both classes with namespace Test\Src; Then how can we create object. if i used as this it throws exception Fatal error: Class 'Test\Src\Second' not found – Bruce May 12 '15 at 19:42
You can get more info in another question on SO http://stackoverflow.com/questions/1830917/how-do-i-use-php-namespaces-with-autoload – Marin Bînzari May 12 '15 at 19:48

php create instance of another class

1 Answers1