JavaScript对象创建及其原型

Question

I create an Object in JavaScript:

var object = {value1 : "value1", value2 : "value2"};

If I now try and count the contents of 'object.prototype' I get the result 0. If I add properties I get the correct result. Am I to take it then that 'object.prototype' is in fact empty?

Thanks!

Answer 1

If you want to iterate through all the properties you assigned to your object, you can just do it with a for..in loop:

for (var prop in object){
    if (object.hasOwnProperty(prop)){
        var propValue = object[prop];
        // ...
    }
}

If you need to count the properties, you can just increment a counter on each iteration.

Answer 2

In Javascript, by DEFAULT only "function objects" have a prototype property..

for example, none of the following have a prototype property by default -

var a = new Object();
var b = {};
var a = new Array();
var b = [];

But,

var a = function() {};

has a prototype property.. and by default -

a.prototype is {constructor : this}