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HomeBackend DevelopmentPHP Tutorialphp 设计模式 之 abstract 抽象类简介

最近正在看 《learning php设计模式》,记录一下自己的笔记

须知
  • 定义为抽象的类不能被实例化
  • 子类必须定义父类中的所有抽象方法
  • 抽象类定义了方法的权限,子类实现时权限必须一致
  • 同 3,类型,所需参数数量必须一致
  • 子类定义了一个可选参数,而父类抽象方法的声明里没有,则两者的声明并无冲突
  • 简单代码示范
    <br />/** * 抽象类 * 如果一个类至少有一个抽象方法,它必然是一个抽象类 * 如果一个类中申明了一个抽象方法,那么继承这个父类的各个子类必须都实现这个方法 */// 定义一个抽象类 用 abstract 定义abstract class AbstractClass{    // PHP 没有抽象属性之说,可以申明一个属性但不指定值,把它当作一个抽象属性    public $storeHere;    // 定义一个抽象函数    abstract public function tick($whatever);}// 继承自抽象类class RunAbstractClass extends AbstractClass{    // 必须实现父类方法    public function tick($whatever){        // 可以使用父类属性 :) 这不废话嘛!这不废话嘛!这不废话嘛!        $this->storeHere = $whatever;        return 'wu wu wu '.$this->storeHere;    }}$test = new RunAbstractClass();echo $test->tick('testing'); // wu wu wu testing
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