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php类和对象的问题

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Jun 23, 2016 pm 02:19 PM

PHP 对象类

请问为何不能
public $mp=new Model("producttype");
这样啊，我在C#里就可以这样的，可以那一个对象但属性的。php里就包错了，为什么啊。

回复讨论(解决方案)

成员属性值必定是一个确定的值，

就是说值类型应该是：基本数据类型，可以是数组，对象不行

C# 是编译执行的，所以可以那样用
php 是解释执行的，在语法分析阶段不可能预知 new Model("producttype") 究竟是什么

其实 C# 在语法分析阶段也是不知道 new Model("producttype") 是什么的
但他还有一个联编过程，可以处理它
php 没有这个联编过程，而是在语法分析后就开始执行了，边执行边解释

哦，谢谢。我明白了

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