PHP abstract class inherits abstract class android abstract class method of abstract class

Reason: uncertainty of the parent class

Why design the abstract class technology?

1.In actual development, we may have such a class, which is the parent class of other classes, but it itself does not need to be instantiated , and its main purpose is to let children Classes are inherited to achieve code reuse and at the same time benefit project designers in designing classes.

2.Keywords:abstract

3.Basic usage:

abstract class class name

{//method

//attribute

function Function name(Parameter list) ; /*abstract modifier

function

function name(parameter list) { echo " This way of writing is wrong!

";//

Because there is an extra method body

} */ } abstract

modified a class, this class is called an abstract class;

abstract

Modify a method, this class is called an abstract method [If it is an abstract method, it cannot have a method body];

4.Notes

:

a

.

Abstract classes can have no abstract methods, and can also have implemented methods (complete functions); b.

Once a method is declared

abstractmethod, the class must be declared as abstract

class , that is, the

abstract class name corresponds to the abstract method; c.If a class inherits an abstract class, it must inherit all of the abstract class

Abstract method, unless it is an abstract class;

Case 1:

abstract class Animal //parent class

{

public $name; protected $price; abstractpublic function cry();

//

There is no method body. This method is mainly for subclasses to implement

} class Dog extends Animal //

subclass

{

public function

cry

()//

subclass inherits parent class method

{echo " Small The dog is barking! The above has introduced PHP abstract classes, including PHP and abstract class content. I hope it will be helpful to friends who are interested in PHP tutorials.