typescript 错误类型错误：无法读取未定义的属性“地图”

ERROR TypeError: Cannot read property 'map' of undefined

提问by mchev

got this error and really don't get why.. I'm trying to display events on angular-calendar : https://mattlewis92.github.io/angular-calendar/#/async-events

得到这个错误，真的不明白为什么..我正在尝试在 angular-calendar 上显示事件：https: //mattlewis92.github.io/angular-calendar/#/async-events

error_handler.ts:1 ERROR TypeError: Cannot read property 'map' of undefined at MapSubscriber.project (planning.component.ts:100) at MapSubscriber._next (map.ts:75) at MapSubscriber.Subscriber.next (Subscriber.ts:95) at MapSubscriber._next (map.ts:80) at MapSubscriber.Subscriber.next (Subscriber.ts:95) at XMLHttpRequest.onLoad (xhr_backend.ts:99) at ZoneDelegate.webpackJsonp.85.ZoneDelegate.invokeTask (zone-mix.js:424) at Object.onInvokeTask (ng_zone.ts:280) at ZoneDelegate.webpackJsonp.85.ZoneDelegate.invokeTask (zone-mix.js:423) at Zone.webpackJsonp.85.Zone.runTask (zone-mix.js:191)

error_handler.ts:1 错误类型错误：无法读取 MapSubscriber.project (planning.component.ts:100) at MapSubscriber._next (map.ts:75) at MapSubscriber.Subscriber.next (Subscriber.ts) 的未定义属性“地图” :95) 在 MapSubscriber._next (map.ts:80) 在 MapSubscriber.Subscriber.next (Subscriber.ts:95) 在 XMLHttpRequest.onLoad (xhr_backend.ts:99) 在 ZoneDelegate.webpackJsonp.85.ZoneDelegate.invokeTask (zone -mix.js:424) at Object.onInvokeTask (ng_zone.ts:280) at ZoneDelegate.webpackJsonp.85.ZoneDelegate.invokeTask (zone-mix.js:423) at Zone.webpackJsonp.85.Zone.runTask (zone- mix.js:191)

component.ts

组件.ts

import { Component, ChangeDetectionStrategy, OnInit } from '@angular/core';
import { Http, URLSearchParams } from '@angular/http';
import { HttpClient } from '@angular/common/http';
import { CustomDateFormatter } from './custom-date-formatter.provider';
import 'rxjs/add/operator/map';
import { Observable } from 'rxjs/Observable';

interface Event {
 id: number;
 title: string;
 start: string;
 end: string;
}

events$: Observable<Array<CalendarEvent<{ event: Event }>>>;

constructor(private http: Http) { }

ngOnInit(): void {
    this.fetchEvents();
}

fetchEvents(): void {

    this.events$ = this.http
        .get(this.apiUrl)
        .map((response) => response.json())
        .map(({ results }: { results: Event[] }) => {
            return results.map((event: Event) => {
                return {
                    title: event.title,
                    start: new Date(event.start),
                    end: new Date(event.end),
                    color: colors.yellow
                };
            });
        });

}

json data from api

来自api的json数据

[
{
"id": 2,
"user_id": 1,
"planning_id": 1,
"start": "2017-09-03T22:00:00.000Z",
"end": "2017-09-06T12:33:46.271Z",
"title": "A 3 day event",
"created_at": "2017-09-05 16:39:47",
"updated_at": "2017-09-05 16:39:47"
},
{
"id": 3,
"user_id": 1,
"planning_id": 1,
"start": "2017-09-03T22:00:00.000Z",
"end": "2017-09-06T12:33:46.271Z",
"title": "A 3 day event",
"created_at": "2017-09-07 13:27:36",
"updated_at": "2017-09-07 13:27:36"
}
]

回答by Francesco Guidi

I know it's old but I found a way to make it work with Angular 5

我知道它很旧，但我找到了一种方法让它与 Angular 5 一起使用

Declare the events this way:

以这种方式声明事件：

asyncEvents$: Observable<CalendarEvent[]>;

Then load your data with HttpClient

然后使用 HttpClient 加载您的数据

Note that I have a DateEventreturned by my API

请注意，DateEvent我的 API 返回了一个

loadEvents() {
    this.asyncEvents$ = this.http.get<DateEvent[]>(YOUR_URL) 
      .map(res => { 
        return res.map(event => { 
          return {
              title: event.label,
              start: new Date(event.startDate),
              color: {primary: event.color, secondary: "#D1E8FF"},
              meta: {
                event
              },
              allDay: true
            };
        });
      });
  }

Then everything works as expected

然后一切都按预期进行

回答by Ganesh Singh

1. ng update
2. ng update @angular/cli
3. ng update @angular/core

1. 更新
2. ng更新@angular/cli
3. ng更新@angular/core

回答by SKL

Remove node_moduleand run npm install. Its solved my issue

删除node_module并运行npm install。它解决了我的问题

回答by SplitterAlex

You have to import the map operator:

您必须导入地图运算符：

import 'rxjs/add/operator/map';

import 'rxjs/add/operator/map';