Javascript 位置 0 Angular2 JSON 中的 SyntaxError 意外标记 u
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SyntaxError unexpected token u in JSON on position 0 Angular2
提问by Astrid Karsten
I tried to make a server with some dummy data.
我试图用一些虚拟数据制作一个服务器。
Here is my System.js Config (since I have a slightly different routing, this seemed to work fine up till now)
这是我的 System.js 配置（因为我的路由略有不同，到目前为止这似乎工作正常）
System.config({
// baseURL to node_modules
baseURL: '/plugins/dashboard/assets/@@version@@/node_modules',
defaultJSExtensions: true
});
System.import('/plugins/dashboard/assets/@@version@@/app/main')
.then(null, console.error.bind(console));
here is my service:
这是我的服务：
import {Injectable} from 'angular2/core';
import {Http, Response} from 'angular2/http';
//import {Observable } from 'rxjs/Observable';
import {Observable} from 'rxjs/Rx';
import {newsLetter} from "../objects/newsLetter";
@Injectable()
export class newsLetterService {
constructor (private http: Http) {}
//Need to change this URL
private _myNewsLetterUrl = "http://epub-core.dev.prisma-it.com:8888/plugins/dashboard/assets/@@version@@/app/data/newsLetter.json"; // URL to web api
getNewsLetter () {
console.log(this._myNewsLetterUrl);
console.log(this.http.get(this._myNewsLetterUrl));
return this.http.get(this._myNewsLetterUrl)
.map(res => <newsLetter[]> res.json().data)
// eyeball objects as json objects in the console | mapping purposes
.do(data => console.log(JSON.parse(JSON.stringify(data))))
.catch(this.handleError);
}
private handleError (error: Response) {
// in a real world app, we may send the error to some remote logging infrastructure
// instead of just logging it to the console
console.error(error);
return Observable.throw(error.json().error || 'Server error');
}
}
however, if I change the console log to console.log(data) it is returning undefined.
但是，如果我将控制台日志更改为 console.log(data)，它将返回 undefined。
I looked everywhere, but none of the answers solved my case. It might be a problem with system js, but since everything else seems to work fine, I really cannot find how to fix this.
我四处看了看，但没有一个答案能解决我的问题。这可能是系统 js 的问题，但由于其他一切似乎都可以正常工作，我真的找不到如何解决这个问题。
This is the response in the console:
这是控制台中的响应：
console response:
控制台响应：
回答by Günter Z?chbauer
JSON.stringify(undefined)results in invalid JSON, this is why JSON.parse(JSON.stringify(data))throws.
JSON.stringify(undefined)导致无效的 JSON，这就是JSON.parse(JSON.stringify(data))抛出的原因。
You might change your code to
您可以将代码更改为
JSON.parse(JSON.stringify(data || null ))
