Internal Control of Object Creation

When you create a new object, i.e. instantiate it with the keyword new, PHP gives you a constructor. You can use this constructor to control what happens when the object is created.

Why would you want to do that?

An object should be created in a known starting state. This approach makes sure the object is ready to use. You pass in the starting information and then let the object initialize itself. You can let it setup and set the properties as well as run the initialization processes.

The other reason is that the implementation, i.e. the external application code (outside of the object), should know very little about how to use and work with the object. It should have to set up the object. It should be done for you when you use the object. You want to hide away (abstract) the complexity.

You’ll also learn about a shorthand method of using a variable to point to the property, e.g. $this->{$property} = $value;. This technique saves you code and redundancy.

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