什么时候应该在类中设置变量

Question

Hay, when should variables be set within a PHP class?

<?php
    class MyClass {
        var $my_var;    // here? like var $my_var = null;
        function __construct(){
            $this->my_var = null; // or here?
        }
    }
?>

Answer 1

It depends what you want to initialise them to. I prefer to initialise them when they're declared if possible, but if they need to be, for example, the result of a method call, then you'll need to initialise them in the constructor.