How to create PHP method linking?

Question

I've seen other objects that do this:

$obj->method1()->method2();

How do I do that? Is each function just modifying the pointer of an object or returning a pointer?

I don't know the proper term for this style -- if anyone could help me with that, it would be great.

Answer 1

Fluid interface.

Simply set your object's method1() to return $this

Answer 2

This is achieved by returning $this at the end of each function, thus giving a chainable reference.

class MyClass {
    public function method1() {
        //...
        return $this;
    }
    public function method2() {
        //...
        return $this;
    }
}

Answer 3

Lets say you have a Person class. You will have your methods doing something like that:

public function setName($name)
{
    $this->name = $name;
    return $this; // We now return $this (the Person)
}

Download Zend Framework and check some part of the code - you can learn a lot from there.

Answer 4

I refer to this as method chaining. See http://www.devshed.com/c/a/PHP/Method-Chaining-in-PHP-5/1/

also inside your method

public function method1()
   // do stuff

   return $this;
}