PHP Object-oriented (i)

I. Classes and objects

1, what is a class: class is a description of a class of things, is an abstract, conceptual definition. is a collection of objects with some of the same properties and functional behavior.

In object-oriented programming, a class should have a class name and include two main parts: the title of the property and the description of the function.

2. An object is an entity/instance used in the system to describe a customer's view of things.

3, the instantiation of the class result is the object, and the abstract of a class of objects is the classes. Class describes a set of objects that have the same attributes (attributes) and the same behavior (methods).

Ii. declarations of classes and creation of objects

1. Declaration of class

// declaring classes class class Name {  //Code (Properties  , Methods)...}

　Specification: Class name capitalization, camel-like syntax

2. Create objects

$ object Variable New class name ();

　　

Iii. properties and methods of classes

Property (also known as a member variable of a class), a common property in a class.

Declaring a property must be decorated with one of the public/private/protected to define the access rights for the variable.

Method (a member function of a class), the functional behavior in a class, by declaring a function in a class definition, that is, the method of the class that was created.

　　

1. Access by reference variable (object)

First instantiate an object, $variable = new ClassName (), and then use the operator "-" to complete access to the object member properties and member methods.

Access properties: Objects, properties. "$variable->name;"

Modify property: Object--property = new value. "$variable->name = ' newName ';"

Access method: Object---method "$variable->method ();"

2. Intra-class access

Internal Access with keyword $this

Access properties: $this-Properties; "$this->name;"

Modify Property: $this-property = new value; "$this->name = ' newName ';"

Access method: $this-to method; "$this->method ();"

For example:

<?PHPclassperson{ Public $name;//Defining Properties      Public $age;//Defining Properties      Public functionSay () {//Create a method        Echo' My name is '.$this->name. "And my age is".$this->age. " <br/> "; }      Public functionSetName ($name= ' wuming ') {//ways to change the Age property         $this->name =$name; }      Public functionSetage ($age=18){        $this->age =$age; } } $person 1=NewPerson ();//instantiating the person class $person 1->setname (' Xiaozu '); Calling Methods$person 1->setage (24); Echo  $person 1->say (); ?>

PHP Object-oriented (i)