如何获取 JavaScript 对象的类? [英] How to get a JavaScript object's class?

问题描述

我创建了一个 JavaScript 对象，但如何确定该对象的类?

I created a JavaScript object, but how I can determine the class of that object?

我想要类似于 Java 的 .getClass() 方法.

I want something similar to Java's .getClass() method.

推荐答案

Java 的 getClass() 在 JavaScript 中.这主要是因为 JavaScript 是一种基于原型的语言，而 Java 是一种<一个 href="http://en.wikipedia.org/wiki/Class-based_programming" rel="noreferrer">基于类 一个.

There's no exact counterpart to Java's getClass() in JavaScript. Mostly that's due to JavaScript being a prototype-based language, as opposed to Java being a class-based one.

根据您需要 getClass() 的用途，JavaScript 中有几个选项:

Depending on what you need getClass() for, there are several options in JavaScript:

• typeof
• instanceof
• obj.<代码>构造函数
• func.prototype, proto.isPrototypeOf

几个例子:

function Foo() {}
var foo = new Foo();

typeof Foo;             // == "function"
typeof foo;             // == "object"

foo instanceof Foo;     // == true
foo.constructor.name;   // == "Foo"
Foo.name                // == "Foo"    

Foo.prototype.isPrototypeOf(foo);   // == true

Foo.prototype.bar = function (x) {return x+x;};
foo.bar(21);            // == 42

注意:如果您使用 Uglify 编译代码，它将更改非全局类名称.为了防止这种情况，Uglify 有一个 --mangle 参数，您可以将其设置为false 使用 gulp 或 咕噜声.

Note: if you are compiling your code with Uglify it will change non-global class names. To prevent this, Uglify has a --mangle param that you can set to false is using gulp or grunt.

这篇关于如何获取 JavaScript 对象的类?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！