Question

以下是使用＆＃39; toPromise＆＃39;时出现的错误。在POST电话：

XMLHttpRequest无法加载http://jsonplaceholder.typicode.com/posts。从＆＃39; http://jsonplaceholder.typicode.com/posts＆＃39;重定向至＆＃39; https://captcha.gecirtnotification.com/pitc/?url=http%3a%2f%2fjsonplacehold ...212596678@ge.com& LANG = EN_US＆安培; ZSQ = QZsC6JP75b8Z54VNTsJSKHnnWH0WsC6JPMpb6Vszsq＆＃39; 已被CORS政策阻止：请求需要预检，即不允许遵循跨源重定向。

我正在对jsonplaceholders模拟API（http://jsonplaceholder.typicode.com/）进行基本的POST调用。

使用＆＃39; toPromise＆＃39;时，我只会收到上述错误。实现。它在使用Observable时有效。我不确定承诺/可观察分辨率如何/为何影响实际的POST调用和/或预检调用。

这（使用toPromise）失败：

public testPostCall(): any {
    let url = 'http://jsonplaceholder.typicode.com/posts';
    let headers = new Headers({ 'Content-Type': 'application/json' });
    let options = new RequestOptions({ headers: headers });
    let payload = {
        "userId": 1,
        "id": undefined,
        "title": "Test API Title",
        "body": "quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto"
    };

    return this.http.post(url, payload, options)
        .toPromise()
        .then((response: Response) => {
            console.log('post response', response);
            return response.json();
        });
}

这（使用Observables）有效：

public testPostCall(): any {
    let url = 'http://jsonplaceholder.typicode.com/posts';
    let headers = new Headers({ 'Content-Type': 'application/json' });
    let options = new RequestOptions({ headers: headers });
    let payload = {
        "userId": 1,
        "id": undefined,
        "title": "Test API Title",
        "body": "quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto"
    };

    return this.http.post(url, payload, options)
    .map((response: Response) => {
        console.log('post response', response);
        return response.json();
    })
    .catch(this.handleError);
}

以下是导入：

import { Injectable } from '@angular/core';
import { Http, RequestOptionsArgs, Response, Headers, RequestOptions } from '@angular/http';
import { Observable, BehaviorSubject } from 'rxjs';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/toPromise';

只有在使用＆＃39; toPromise＆＃39;时才会出现Angular 2 CORS问题。但不是Observables

0 个答案: