PHP OOP: Chainable objects?

Question

I have tried to find a good introduction on chainable OOP objects in PHP, but without any good result yet.

How can something like this be done?

$this->className->add('1','value'); $this->className->type('string'); $this->classname->doStuff();

Or even: $this->className->add('1','value')->type('string')->doStuff();

Thanks a lot!

Gumbo · Accepted Answer · 2010-05-28 14:44:27Z

The key is to return the object itself within each method:

class Foo { function add($arg1, $arg2) { // … return $this; } function type($arg1) { // … return $this; } function doStuff() { // … return $this; } }

Every method, that returns the object itself, can be used as an intermediate in a method chain. See Wikipedia’s article on Method chaining for some further details.

Vic · Accepted Answer · 2010-05-28 14:39:18Z

just return $this in the add() and type() methods:

function add() { // other code return $this; }

Mark Baker · Accepted Answer · 2010-05-28 15:07:28Z

5

Another term for this is the Fluent Interface

answered May 28, 2010 at 15:07

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1 Comment

Adding a note: method chaining is but one technique in creating a fluent interface.