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HomeBackend DevelopmentPHP TutorialPHP class declaration and object instantiation

<?php 
/* 类的声明 
* 1.你要开发的是什么,确定写什么类 
* 2.类中的成员一定要属于这个类 
* [修饰类的关键字] class 类名{ 
* 成员属性: 
* 成员方法: 
* } 
* 3.在类中声明成员属性时,前面必须有修饰词,当不确定使用哪个词时,使用var或public 
* 一个文件只保存一个类,文件名中包含类名,文件:类名.class.php 
* 类名的写法: 
* 变量:aaaBbbCcc 
* 函数:aaaBbbCcc 
* 常量:AAABBBCCC 
* 类名:AaaBbbCcc 
* 4.类中的成员属性,如果创建多个对象时,每个对象有不同的属性值时,不要直接给初值,在创建好对象之后再给值 
* 
* 
* 通过类来实例化对象 
* 1.使用的是new新建一个对象,加上类名,就是创建哪个类的对象 
* $对象引用=new 类名; 
* 2.只要有一个new 关键字就是创建一个对象,创建一个对象就是在内存中分配了一个空间 
* 
* 只有对象才在内存有存储空间 
* 
* 对象的作用 
* 
* 对象在内存中的分配 
* 
* 对象的使用 
* 对象中的成员必须通过对象的引用来访问 
* 对象->成员 
* 
* 对象->成员属性 
* 对象->成员方法 
* 
* 
* 
*/ 
//类的声明(电话类) 
class Phone{ 
//声明属性 
var $pinPai; 
var $color; 
var $batteryCapacity; 
var $screenSize; 
//成员方法 
function call(){ 
} 
function message(){ 
} 
function playMusic(){ 
} 
function photo(){ 
} 
} 
//类的实例化 
class Person{ 
var $name; 
var $age; 
var $sex; 
function say(){ 
} 
function eat(){ 
} 
function run(){ 
} 
} 
//实例化 
$p1=new Person; 
$p2=new Person; 
$p3=new Person; 
//访问对象的成员 
$p1->name="zhangsan"; 
echo $p1->name; 
?>

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