How to define a class in php

PHP class definition

The usual syntax format of PHP definition class is as follows:

<?php
class phpClass {
  var $var1;
  var $var2 = "constant string";
  
  function myfunc ($arg1, $arg2) {
     [..]
  }
  [..]
}
?>

The analysis is as follows:

类使用 class 关键字后加上类名定义。
类名后的一对大括号({})内可以定义变量和方法。
类的变量使用 var 来声明, 变量也可以初始化值。
函数定义类似 PHP 函数的定义，但函数只能通过该类及其实例化的对象访问。

Example

<?php
class Site {
  /* 成员变量 */
  var $url;
  var $title;  
  /* 成员函数 */
  function setUrl($par){
     $this->url = $par;
  }
  function getUrl(){
     echo $this->url . PHP_EOL;
  } 
  function setTitle($par){
     $this->title = $par;
  }  
  function getTitle(){
     echo $this->title . PHP_EOL;
  }
}
?>

After the class is created, we can use the new operator to instantiate objects of this class:

$runoob = new Site;
$taobao = new Site;
$google = new Site;

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