Methods are SPL procedures or functions defined in an object type. Methods are categorized into three general types:
- Member methods — Procedures or functions that operate in the context of an object instance. Member methods have access to and can change the attributes of the object instance on which they're operating.
- Static methods — Procedures or functions that operate independently of any particular object instance. Static methods don't have access to and can't change the attributes of an object instance.
- Constructor methods — Functions used to create an instance of an object type. A default constructor method is always provided when an object type is defined.