您如何指定一个返回观测值的API?

最重要的是, .

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简而言之,这是您需要的类型脚本代码。

import { Observable } from 'rxjs';
import { Subject } from 'rxjs';
import { Observer } from 'rxjs';

import * as socketIoClient from 'socket.io-client';

export class SocketObs {
    private socket: SocketIOClient.Socket;

    private connect = new Subject<any>();
    private disconnect = new Subject<any>();

    constructor(url: string);
    constructor(input: any) {
        this.socket = socketIoClient(input);
        this.socket.on('connect',
            () => {
                this.connect.next();
                // complete to make sure that this event is fired only once
                this.connect.complete();
            }
        );
        this.socket.on('disconnect',
            () => {
                this.disconnect.next();
                // complete to make sure that this event is fired only once
                this.disconnect.complete();
            }
        );

    }

    send(event, message?) {
        this.socket.emit(event, message);
    }
    onEvent(event): Observable<any> {
        return new Observable<any>((observer: Observer<any>) => {
            this.socket.on(event, data => observer.next(data));
        });
    }
    onDisconnect() {
        return this.disconnect.asObservable();
    }
    onConnect() {
        return this.connect.asObservable();
    }

    close() {
        this.socket.close();
    }
}

onEvent