PHP提供了3种类型的访问说明符:公共(public)，私有(private)和受保护(protected)。
公开(public) - 具有此访问修饰符的类(class)成员可以从任何地方公开访问，甚至可以在类(class)范围之外访问。
私人(private) - 使用此关键字的类(class)成员将在类(class)内部访问。它使用类实例的引用保护成员免受外部类访问。
受保护(protected) - 与私有相同，只是允许子类访问受保护的超类成员。
示例1:Public
<?php class demo { public $name="Ajeet"; functiondisp() { echo $this->name."<br/>"; } } class child extends demo { function show() { echo $this->name; } } $obj= new child; echo $obj->name."<br/>"; $obj->disp(); $obj->show(); ?>
输出:
示例2:Private
<?php classLearnfk { private $name="Sonoo"; private function show() { echo "This is private method of parent class"; } } class child extends Learnfk { function show1() { echo $this->name; } } $obj= new child; $obj->show(); $obj->show1(); ?>
输出:
示例3:Protected
输出:
示例4
<?php classLearnfk { public $name="Ajeet"; protected $profile="HR"; private $salary=5000000; public function show() { echo "Welcome : ".$this->name."<br/>"; echo "Profile : ".$this->profile."<br/>"; echo "Salary : ".$this->salary."<br/>"; } } classchilds extends Learnfk { public function show1() { echo "Welcome : ".$this->name."<br/>"; echo "Profile : ".$this->profile."<br/>"; echo "Salary : ".$this->salary."<br/>"; } } $obj= new childs; $obj->show1(); ?>
输出:
