angular - 如何在订阅中添加`map`运算符

Question

在我的组件中，我从父级获取事件。（包装器）但在我发送到模板之前，我需要迭代并在数组中添加日期值。在我通过订阅执行此操作后对我不起作用。

有人告诉我在迭代后重新分配值的正确方法吗？

这是我的尝试：

import { Component, OnInit, ChangeDetectionStrategy, Input  } from '@angular/core';
import { CalendarService } from "./../../services/calendar.service";
import { ModelEvent, EventState } from "./../../models/model.event";
import { CalendarEvent } from 'angular-calendar';
import { colors } from "./../../utilities/colors";
import { setHours, setMinutes, setDate } from 'date-fns';
import { Observable } from 'rxjs';
import { tap, map } from 'rxjs/operators';
declare var $:any;

@Component({
    selector: 'ibo-calendar',
    templateUrl: './ibo-calendar.component.html',
    styleUrls: ['./ibo-calendar.component.scss']
})
export class IboCalendarComponent implements OnInit {

    // events = [];
    eventId:number | null;

    view: string = 'month';
    // viewDate: Date = new Date('August 19, 2018');
    viewDate: Date = new Date()

    @Input() events:Observable<ModelEvent[]>;
    @Input() currentEvent: ModelEvent;

    clickedDate: Date;
    updatedEvents:Observable<ModelEvent[]>;

    constructor(private calendarService:CalendarService) { }

    ngOnInit() {

        this.updatedEvents = this.events.subscribe(events => {
            console.log('events', events); //getting consoled.
            return map(event => { //not works!!
                return {
                    title : event.title,
                    name : event.name,
                    date : new Date()
                }
            })
        })

}

标签： angularobservablerxjs6

Answer 1

对于 RxJS >= 6

import { map } from 'rxjs/operators'; 

尝试：

    this.updatedEvents = this.events.pipe(map(event => {
            return {
                title : event.title,
                name : event.name,
                date : new Date()
            }
        })).subscribe(events => {
           console.log(events)
        })
    })

或者你可以这样做：

    this.updatedEvents = this.events.subscribe(events => {
        this.some_val_to_render_on_html = events.map(event => 
            return {
                title : event.title,
                name : event.name,
                date : new Date()
            }
        })
    })