观察力服务 - 错过 /最佳实践

Question

我正在为两个组件之间的观察服务方法挣扎。我有一个配置文件组件，其中包括设置组件。两者都使用user.service在app.module.ts中定义提供商的服务。提供商尚未定义任何其他地方。因此，当我更改为" settings.component"上的第一个名称并保存时。在我重新加载页面之前，更改不会在profile.com.popents的侧边栏中反映。

下班后：我找到了一个解决方案，可以通过eventemitter进行此操作，该EventEmtter将在更新发生后立即触发。这将解决我上面的问题，但我认为这不是我阅读以下文章的正确方法：

eventemitter的适当使用是什么？

没有事件Emmiter不应该工作吗？

所以我的问题：您将在这种情况下使用哪种方法或最佳实践是什么？当然，我的代码中可能存在问题。我真的很新来。

app.module.ts

在app.module.ts中我定义：

 providers: [UserService]

profile.component.ts

@Component({
    selector: 'app-profile',
    templateUrl: './profile.component.html',
    styleUrls: ['./profile.component.css']
})
export class ProfileComponent implements OnInit {
    user: any;
    Role = Role;
    constructor(private _userService: UserService, ) { }

    ngOnInit() {
        const token = localStorage.getItem('token');
        const role = jwt.decode(token).user.role;
        this._userService.getUser().subscribe(v => { this.user = v; });
        // Event Emmiter Subscription
        this._userService.change.subscribe(v => { this.user = v; });
    }
}

profile.component.html

<div *ngIf="user" class="container mt50">
    <div class="row profile">
        <div class="col-md-3">
            <div class="profile-sidebar">
                <!-- SIDEBAR USERPIC -->
                <div class="profile-userpic">
                    <img gravatar [email]="user.email" [size]="256" class="img-responsive animated bounceIn" alt="">
                </div>
                <!-- END SIDEBAR USERPIC -->
                <!-- SIDEBAR USER TITLE -->
                <div class="profile-usertitle">
                    <div class="profile-usertitle-name">
                        {{ user.firstName }} {{ user.lastName }}
                    </div>
                    <div class="profile-usertitle-job">
                        {{ user.email }}
                    </div>
                </div>
            </div>
        </div>
        <div class="col-md-9">
                <app-profile-settings-admin *ngIf="user.role === Role.ADMINISTRATOR"></app-profile-settings-admin>
        </div>
    </div>
</div>

user.service.ts

@Injectable()
export class UserService {
    public user: any;
    constructor(private http: Http) { }
    // EVENT EMIITER
    public change: EventEmitter<any> = new EventEmitter();
    getUser() {
        const token = localStorage.getItem('token')
            ? '?token=' + localStorage.getItem('token')
            : '';
        return this.http.get('api/user' + token)
            .map((response: Response) => {
                this.user = response.json().obj;
                return this.user;
            })
            .catch((error: Response) => Observable.throw(error.json()));
    }
    updateUser(user) {
        const body = JSON.stringify(user);
        const headers = new Headers({'Content-Type': 'application/json'});
        const token = localStorage.getItem('token')
            ? '?token=' + localStorage.getItem('token')
            : '';
        return this.http.patch('api/user/' + token, body, {headers: headers})
            .map((response: Response) => {
                const result = response.json();
                this.user = result.obj;
                // EMIT EVENT
                this.change.emit(this.user);
                return this.user;
            })
            .catch((error: Response) => Observable.throw(error.json()));
    }
}

profile.settings.admin.component.ts

在该组件中，只有一种表格可以在提交上发射以下代码：

onSubmit() {
    this._userService.updateUser(this.userForm.value)
        .subscribe(
            data => {
                this._toastyService.default('Settings saved!');
                console.log(data);
            },
            error =>{
                this._toastyService.default('Error occured!');
                console.log(error);
            }
        );
}

Answer 1

实时工作示例您无需启动事件即可在组件之间共享(和同步(数据。让Angular服务(和角形式(为您控制：

profile.component

ngOnInit() {
    const token = localStorage.getItem('token');
    const role = jwt.decodeToken(token).user.role;
    this._userService.getUser().subscribe(v => {
        this.user = v; 
    });
}

user.service

getUser() {
    const token = localStorage.getItem('token')
        ? '?token=' + localStorage.getItem('token')
        : '';
    return this.http.get('api/user' + token)
        .pipe(map((user: HttpResponse<any>) => {
            this.user = user;
                return this.user;
            }),
        catchError((error: HttpErrorResponse) => Observable.throw(error)))
}
updateUser(user) {
    const body = JSON.stringify(user);
    const headers: HttpHeaders =  new HttpHeaders({'Content-Type': 'application/json'});
    const token = localStorage.getItem('token')
        ? '?token=' + localStorage.getItem('token')
        : '';
    return this.http.patch('api/user/' + token, body, {headers})
        .pipe(map((user: HttpResponse<any>) => {
            this.user = user;
            return this.user;
        }),
        catchError((error: HttpErrorResponse) => Observable.throw(error)));
}

profile.settings.admin.component.ts

ngOnInit() {
    this._userService.getUser().subscribe((user: User) => {
        this.user = user;         
    });
}
onSubmit() {
    this._userService.updateUser(this.user)
        .subscribe(
            data => {
                this._toastyService.default('Settings saved!');
                console.log(data);
            },
            error =>{
                this._toastyService.default('Error occured!');
                console.log(error);
            }
        );
}

profile.settings.admin.component.html

<form #userForm="ngForm">
    <div class="form-group">
        <label for="name">Name</label>
        <input type="text" class="form-control" id="name" aria-describedby="nameHelp" 
            placeholder="enter name" [(ngModel)]="user.name" name="name" required #name="ngModel">
        <div [hidden]="name.valid || name.pristine"
            class="alert alert-danger">
            Name is required
        </div>
    </div>
     <div class="form-group">
        <label for="lastName">Last Name</label>
        <input type="text" class="form-control" id="lastName" aria-describedby="lastNameHelp" 
            placeholder="enter last name" [(ngModel)]="user.lastName" name="lastName" required #lastName="ngModel">
        <div [hidden]="lastName.valid || lastName.pristine"
            class="alert alert-danger">
            last Name is required
        </div>
    </div>
    <div class="form-group">
        <label for="email">Email</label>
        <input type="email" class="form-control" id="email" aria-describedby="emailHelp" 
            placeholder="enter email" [(ngModel)]="user.email" name="email" required #email="ngModel">
        <div [hidden]="email.valid || email.pristine"
            class="alert alert-danger">
            email is required
        </div>
    </div>
    <button type="submit" class="btn btn-success" (click)="onSubmit()" >Submit</button>
</form>