Ionic2 离子2提供者

我正在使用将我的应用程序从

Ionic 2.0.0-beta.20升级到
Ionic 2.0.0-rc.3

我有一个关于
提供商
的问题，称为
评级服务
，对此我有点困惑，如果有人能提供帮助，我将不胜感激

问题

我在
app.module.ts
中遇到以下错误

[ts] Argument of type '{ declarations: any[]; imports: ModuleWithProviders[]; bootstrap: typeof IonicApp[]; entryCompone...' is not assignable to parameter of type 'NgModule'.
       Types of property 'providers' are incompatible.
         Type '{ provide: typeof ErrorHandler; useClass: typeof IonicErrorHandler; RatingService: typeof RatingS...' is not assignable to type 'Provider[]'.
           Type '{ provide: typeof ErrorHandler; useClass: typeof IonicErrorHandler; RatingService: typeof RatingS...' is not assignable to type 'Provider'.
             Object literal may only specify known properties, and 'RatingService' does not exist in type 'Provider'.

我认为我需要为每个
提供者使用
提供：
和
使用类：
，但我不确定这些值应该是什么

代码

应用程序模块.ts

  import { RatingService } from '../pages/service/ratingService';
    ...
  providers: [{ provide: ErrorHandler, 
    useClass: IonicErrorHandler, 
    RatingService,
    JobService, 
    UtilityService, 
    ...

import { Injectable, Inject } from "@angular/core";
import { RatingModel } from '../model/RatingModel';
import { NavController } from 'ionic-angular';
import { Http, Headers } from "@angular/http"
import { ParentService } from "../service/parentService";
import 'rxjs/add/operator/map';

@Injectable()
export class RatingService extends ParentService {

    public BASE_URI: String = super.getBaseUrl()+'/rating';

    public http: Http = null;

    constructor( @Inject(Http) http: Http) {
        super();
        this.http = http;
    }

    getRatingRange(firstResult: number, maxResults: number): Promise<RatingModel[]> {
        return new Promise<RatingModel[]>(resolve => {
            this.getRatingRangeHttpCall(firstResult, maxResults).subscribe(
                data => {
                    var ratingModels: RatingModel[] = [];
                    for (var index = 0; index < data.length; index++) {
                        var element = data[index];
                        ratingModels.push(element);
                    }
                    resolve(ratingModels);
                },
                error => alert('RatingRangeDataPromise(' + firstResult + ', ' + maxResults + ') Data not available. Please try again.\n' + error),
                () => {
                });
        });
    }

    getRatingForJobRange(firstResult: number, maxResults: number, jobId: number): Promise<RatingModel[]> {
        return new Promise<RatingModel[]>(resolve => {
            this.getRatingRangeForJobHttpCall(firstResult, maxResults, jobId).subscribe(
                data => {
                    var ratingModels: RatingModel[] = [];
                    for (var index = 0; index < data.length; index++) {
                        var element = data[index];
                        ratingModels.push(element);
                    }
                    resolve(ratingModels);
                },
                error => alert('RatingForJobRange(' + firstResult + ', ' + maxResults + ', ' + jobId + ') Data not available. Please try again.\n' + error),
                () => {
                });
        });
    }

    saveRating(ratingModel: RatingModel): Promise<RatingModel> {
        return new Promise<RatingModel>(resolve => {
            this.saveRatingHttpCall(ratingModel).subscribe(
                data => {
                    resolve(data);
                },
                error => alert('Save Unsuccesfull.\n' + error),
                () => {

                });
        });
    }

    getRating(id: number): Promise<RatingModel> {
        return new Promise<RatingModel>(resolve => {
            this.getRatingHttpCall(id).subscribe(
                data => {
                    resolve(data);
                },
                error => alert('getRating Data not available. Please try again.\n' + error),
                () => {
                    //console.log("Finished getRating");
                });
        });
    }

    public getRatingRangeHttpCall(firstResult: number, maxResults: number) {
        return this.http.get(this.BASE_URI + '/list/range/' + firstResult + '/' + maxResults)
            .map(res => res.json());
    }

    public getRatingRangeForJobHttpCall(firstResult: number, maxResults: number, jobId: number) {
        return this.http.get(this.BASE_URI + '/list/range/' + firstResult + '/' + maxResults + '/' + jobId)
            .map(res => res.json());
    }

    public saveRatingHttpCall(ratingModel: RatingModel) {
        var headers = new Headers();
        headers.append('Accept', 'application/json');
        headers.append('Content-Type', 'application/json');
        return this.http.post(this.BASE_URI + '/save', ratingModel, {
            headers: headers
        })
            .map(res => res.json());
    }

    public getRatingHttpCall(id: number) {
        return this.http.get(this.BASE_URI + '/list/' + id)
            .map(res => res.json());
    }

}

import { Injectable, Inject } from "@angular/core";

@Injectable()
export class ParentService {

    public PARENT_BASE_URI: string = 'http://localhost:8080/jbosswildfly';
    //public PARENT_BASE_URI: string = 'http://jbosswildfly-easypeasy.rhcloud.com';

    constructor() {

    }

    public getBaseUrl(): string {
        return this.PARENT_BASE_URI;
    }
}

评级服务.ts

  import { RatingService } from '../pages/service/ratingService';
    ...
  providers: [{ provide: ErrorHandler, 
    useClass: IonicErrorHandler, 
    RatingService,
    JobService, 
    UtilityService, 
    ...

import { Injectable, Inject } from "@angular/core";
import { RatingModel } from '../model/RatingModel';
import { NavController } from 'ionic-angular';
import { Http, Headers } from "@angular/http"
import { ParentService } from "../service/parentService";
import 'rxjs/add/operator/map';

@Injectable()
export class RatingService extends ParentService {

    public BASE_URI: String = super.getBaseUrl()+'/rating';

    public http: Http = null;

    constructor( @Inject(Http) http: Http) {
        super();
        this.http = http;
    }

    getRatingRange(firstResult: number, maxResults: number): Promise<RatingModel[]> {
        return new Promise<RatingModel[]>(resolve => {
            this.getRatingRangeHttpCall(firstResult, maxResults).subscribe(
                data => {
                    var ratingModels: RatingModel[] = [];
                    for (var index = 0; index < data.length; index++) {
                        var element = data[index];
                        ratingModels.push(element);
                    }
                    resolve(ratingModels);
                },
                error => alert('RatingRangeDataPromise(' + firstResult + ', ' + maxResults + ') Data not available. Please try again.\n' + error),
                () => {
                });
        });
    }

    getRatingForJobRange(firstResult: number, maxResults: number, jobId: number): Promise<RatingModel[]> {
        return new Promise<RatingModel[]>(resolve => {
            this.getRatingRangeForJobHttpCall(firstResult, maxResults, jobId).subscribe(
                data => {
                    var ratingModels: RatingModel[] = [];
                    for (var index = 0; index < data.length; index++) {
                        var element = data[index];
                        ratingModels.push(element);
                    }
                    resolve(ratingModels);
                },
                error => alert('RatingForJobRange(' + firstResult + ', ' + maxResults + ', ' + jobId + ') Data not available. Please try again.\n' + error),
                () => {
                });
        });
    }

    saveRating(ratingModel: RatingModel): Promise<RatingModel> {
        return new Promise<RatingModel>(resolve => {
            this.saveRatingHttpCall(ratingModel).subscribe(
                data => {
                    resolve(data);
                },
                error => alert('Save Unsuccesfull.\n' + error),
                () => {

                });
        });
    }

    getRating(id: number): Promise<RatingModel> {
        return new Promise<RatingModel>(resolve => {
            this.getRatingHttpCall(id).subscribe(
                data => {
                    resolve(data);
                },
                error => alert('getRating Data not available. Please try again.\n' + error),
                () => {
                    //console.log("Finished getRating");
                });
        });
    }

    public getRatingRangeHttpCall(firstResult: number, maxResults: number) {
        return this.http.get(this.BASE_URI + '/list/range/' + firstResult + '/' + maxResults)
            .map(res => res.json());
    }

    public getRatingRangeForJobHttpCall(firstResult: number, maxResults: number, jobId: number) {
        return this.http.get(this.BASE_URI + '/list/range/' + firstResult + '/' + maxResults + '/' + jobId)
            .map(res => res.json());
    }

    public saveRatingHttpCall(ratingModel: RatingModel) {
        var headers = new Headers();
        headers.append('Accept', 'application/json');
        headers.append('Content-Type', 'application/json');
        return this.http.post(this.BASE_URI + '/save', ratingModel, {
            headers: headers
        })
            .map(res => res.json());
    }

    public getRatingHttpCall(id: number) {
        return this.http.get(this.BASE_URI + '/list/' + id)
            .map(res => res.json());
    }

}

import { Injectable, Inject } from "@angular/core";

@Injectable()
export class ParentService {

    public PARENT_BASE_URI: string = 'http://localhost:8080/jbosswildfly';
    //public PARENT_BASE_URI: string = 'http://jbosswildfly-easypeasy.rhcloud.com';

    constructor() {

    }

    public getBaseUrl(): string {
        return this.PARENT_BASE_URI;
    }
}

更新

我已将代码更改为以下内容，我将对其进行测试，看看它是否有效：

  providers: [
    { provide: ErrorHandler, useClass: IonicErrorHandler}, 
    { provide: RatingService, useClass: RatingService}, 
    { provide: JobService, useClass: JobService}, 
    { provide: UtilityService, useClass: UtilityService}
  ]

应该是：

providers: [{ provide: ErrorHandler, 
useClass: IonicErrorHandler}, 
RatingService,
JobService, 
UtilityService,

应该是：

providers: [{ provide: ErrorHandler, 
useClass: IonicErrorHandler}, 
RatingService,
JobService, 
UtilityService,

如果意外使用，也会出现此错误

import RatingService from '../pages/service/ratingService';  

而不是

import { RatingService } from '../pages/service/ratingService';

这个输入错误花费了我2个小时，所以我添加这个答案，希望它能让其他人免于同样的挫折。
如果您不小心使用

import RatingService from '../pages/service/ratingService';  

而不是

import { RatingService } from '../pages/service/ratingService';

那个打字错误花了我2个小时，所以我添加这个答案，希望它能让其他人免于同样的挫折。
是否应该用
}
关闭
{provide:…useClass..
呢？（不确定，我自己没有这样使用过它）{code>{provide:…useClass..
是否应该用一个
}
来关闭？（不确定，我自己没有这样使用过它。）