php构造函数的继承方法,php构造函数继承
php构造函数的继承方法,php构造函数继承
本文实例讲述了php构造函数的继承方法。分享给大家供大家参考。具体如下:
第一种情况:子类没有定义构造函数时,默认继承。例子:
<?php class A{ public $name; function __construct(){ echo $this->name="小强"; } } class B extends A{ } $bb = new B(); ?>
输出结果:小强
第二种情况:子类定义了构造函数,则不会被继承。实例:
<?php class A{ public $name; function __construct(){ echo $this->name="小强"; } } class B extends A{ function __construct(){ echo "BBBBBB子类"; } } $bb = new B(); ?>
输出结果:BBBBBB子类
第三种情况:如果需要调用父类的构造函数,则可以使用:parent::父类函数 或 父类名::父类函数。
希望本文所述对大家的php程序设计有所帮助。

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