Question

下午好！我是Angular 2的新手，所以如果我的问题是通用的，我很抱歉。我无法弄清楚如何处理API响应。

我的NodeJS Server API功能是（已检查并正常工作）：

router.get('/appointment/:iatreio/:time', function(req, res, next) {
   var paramIatreio = req.params.iatreio;
   var paramTime = req.params.time;

   db.appointments.findOne({iatreio: paramIatreio, time: req.params.time}, function(err, resultFound) {      
     if (err) { res.send(err); }
     if (resultFound) {
        res.json(true);  // 1st Question: For best practice, res.json(true) or res.send(true)? 
     } else {
        res.json(false);
     }
   });
});

我的Angular2服务：

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

@Injectable()
export class AppointmentService {
   constructor(private http: Http) { }
   isBooked(iatreio: string, time: string): Observable<boolean> {
      return this.http
                 .get('http://localhost:3000/appointment/'+iatreio+'/'+time)
                 .map(); //2nd Question: What inside map()?
   }
} // end of Service

组件功能

isBooked(selectedIatreio: string, selectedTime: string): boolean {
this.appointmentService
    .isBooked(selectedIatreio, selectedTime)
    .subscribe(() => {}); //3rd Question: What inside subscribe()?
}

我的最终目标是调用我的Component的“isBooked（...）”函数并返回true或false。我在Angular2网站的例子中看到了代码，但我对我的情况有点困惑。

服务函数可以直接返回true或false值，还是必须是Observable？ Map（）函数是必要的??

一般来说，我的想法是正确的？或者我的目标可以更轻松地完成？

非常感谢你的时间!!

Answer 1

map用于将响应转换为您要查找的模型

isBooked(iatreio: string, time: string): Observable<boolean> {
      return this.http
                 .get('http://localhost:3000/appointment/'+iatreio+'/'+time)
                 .map((response)=><boolean>response.json()); 
   }

subscribe将返回服务发出的数据

isBooked(selectedIatreio: string, selectedTime: string): boolean {
this.appointmentService
    .isBooked(selectedIatreio, selectedTime)
    .subscribe((data) => { 
          //your operation
          console.log(data);
     }); 
}

Angular2 - 处理API响应

1 个答案: