Several ways to define classes and objects (1/4)

means that you do not need to check the object type before the program runs, as long as you check that the object supports attributes and methods. You can perform a large number of operations on an object without any penalty before binding.
The above code appears in the "pre-declaration" phenomenon, we can greatly use the "late binding" mechanism to explain. In the scope of a function, all variables are "late bound". That is, the declaration is top-level. So the code above is consistent with the following:
Copy code code as follows:

var a = ' global ';
(function () {
var A;
alert (a);
A = ' local ';
})();

Only a declaration was made to a before alert (a) and no value was assigned. So the results are predictable.

<!--digression to this end-->
RT: What this article is saying is that in the web effects, I know several ways to define classes and objects: <! --statement: Most of the following comes from "JavaScript advanced Programming", but the individual narrative way is different-->
"Direct Volume Method"
Using direct volume to build objects is the most basic way, but there are many drawbacks.
Copy code code as follows:

var obj = new Object;
Obj.name = ' sun ';
Obj.showname = function () {
Alert (' THIS.name ');
}

We built an object obj, which has a property name, a method showname. But what if we're going to build a similar object? Do you want to repeat it again?
No! , we can implement it with a factory function that returns a particular type of object. Like a factory, the output of an assembly line is the specific type of result we want.
"Factory mode"
Copy code code as follows:

function Createobj (name) {
var tempobj = new Object;
Tempobj.name = name;
Tempobj.showname = function () {
alert (this.name);
};
return tempobj;
}
var obj1 = createobj (' Obj_one ');
var obj2 = createobj (' Obj_two ');

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