.json（）函数在Angular2中做什么？

Question

What does the .json() function in http requests in Angular2 do?

Example code:

this.http.get('http://localhost:8080/getName')
.subscribe(res => this.names = res.json());

I guess it's similar to javascript's JSON.parse() ?

Answer 1

This function takes a response from the Http call, and parses it (just like JSON.parse(..)). Notice, if the return is not json, it will throw an error.

Answer 2

You can check the source code to see what it does. But as @uksz said, it just parses the json, using JSON.parse

The source code is this:

    /**
     * Attempts to return body as parsed `JSON` object, or raises an exception.
     */
    Body.prototype.json = function () {
        if (typeof this._body === 'string') {
            return JSON.parse(this._body);
        }
        if (this._body instanceof ArrayBuffer) {
            return JSON.parse(this.text());
        }
        return this._body;
    };