在Function.prototype.method中返回什么呢？ [英] What does return this in Function.prototype.method do?

问题描述

我刚开始阅读JavaScript：好的部分，我已经对Function.prototype.method中的'返回'做了什么感到困惑？我理解这个和回归是如何运作的。 'this'本质上是当前对象的指针，'return'只是在输出一个值时退出函数，如果你描述的话;在我们的例子中，'this'。

I just started reading JavaScript: The Good Parts and I'm already confused by what 'return this' does in Function.prototype.method? I understand how 'this' and 'return' works. 'this' is essentially a pointer for the current object and 'return' simply exits the function while outputting a value if you described any; in our case, 'this'.

这是我引用的代码。

Function.prototype.method = function(name, func) {
    this.prototype[name] = func;
    return this;
}

/* SIMPLE CONSTRUCTOR */
function Person(name, age) {
    this.name = name;
    this.age = age;
}

/* ADD METHODS */
Person.method('getName', function() { return this.name; });
Person.method('getAge', function() { return this.age; });

var rclark = new Person('Ryan Clark', 22);

console.log(rclark.getName()); // string(Ryan Clark)
console.log(rclark.getAge()); // number(22)

我试图省略'return this'以查看代码是否会破坏但是它没有？究竟什么'回归'呢？我将继续阅读这本书，但我想确保我理解一切。任何帮助将不胜感激。

I tried omitting 'return this' to see if the code would break but it doesn't? What exactly does 'return this' do? I'll keep progressing through this book but I want to make sure I'm understanding everything. Any help will be appreciated.

推荐答案

它允许链接，所以你可以做这样的事情：

It allows for chaining so you can do something like this:

/* ADD METHODS */
Person.method('getName', function() { return this.name; })
      .method('getAge', function() { return this.age; });

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