Angular 4“不能绑定到'ng模型'，因为它不是'input'的已知属性。[副本]

Question

这似乎是一个流行的问题，但解决方案都建议导入FormsModule，这是正在做的。

<label for="city">City</label>
<input type="text" id="city" [ERROR ->][(ngModel)]="chosenCity">
<input type="button" value="Get Weather" (click)="getWeather(chosenCity)" "):

js prettyprint-override">import { Component } from '@angular/core';
import { Http } from '@angular/http';

@Component({
    selector: 'weather',
    templateUrl: './weather.component.html'
})
export class WeatherComponent {
    public weather: Weather;

    constructor( private http: Http) {
    }

    public getWeather(chosenCity: string): void {
        this.http.get('/api/weather/city/' + chosenCity).subscribe(result => {
            this.weather = result.json();
        });
    }
}

interface Weather {
    temp: string;
    summary: string;
    city: string;
}

<h1>Weather check</h1>

<label for="city">City</label>
<input type="text" id="city" [(ngModel)]="chosenCity">
<input type="button" value="Get Weather" (click)="getWeather(chosenCity)" />


<div *ngIf="weather">
    <h3>Weather for {{weather.city}}</h3>

    <table class="table table-bordered table-striped">
        <thead>
            <tr>
                <th>Temp</th>
                <th>Summary</th>
            </tr>
        </thead>
        <tbody>
            <tr>
                <td>{{weather.temp}}</td>
                <td>{{weather.summary}}</td>
            </tr>
        </tbody>
    </table>
</div>

app.module.shared.ts如下所示：

import { NgModule } from '@angular/core';
import { RouterModule } from '@angular/router';

import { AppComponent } from './components/app/app.component'
import { NavMenuComponent } from './components/navmenu/navmenu.component';
import { HomeComponent } from './components/home/home.component';
import { FetchDataComponent } from './components/fetchdata/fetchdata.component';
import { CounterComponent } from './components/counter/counter.component';
import { HelloWorldComponent } from './components/helloworld/helloworld.component';
import { WeatherComponent } from './components/weather/weather.component';

export const sharedConfig: NgModule = {
    bootstrap: [ AppComponent ],
    declarations: [
        AppComponent,
        NavMenuComponent,
        CounterComponent,
        FetchDataComponent,
        HomeComponent,
        HelloWorldComponent,
        WeatherComponent
    ],
    imports: [
        RouterModule.forRoot([
            { path: '', redirectTo: 'home', pathMatch: 'full' },
            { path: 'home', component: HomeComponent },
            { path: 'counter', component: CounterComponent },
            { path: 'fetch-data', component: FetchDataComponent },
            { path: 'hello', component: HelloWorldComponent },
            { path: 'weather', component: WeatherComponent },
            { path: '**', redirectTo: 'home' }
        ])
    ]
};

app.module.client.ts文件如下所示：

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { HttpModule } from '@angular/http';
import { sharedConfig } from './app.module.shared';
@NgModule({
    bootstrap: sharedConfig.bootstrap,
    declarations: sharedConfig.declarations,
    imports: [
        BrowserModule,
        HttpModule,
        FormsModule,
        ReactiveFormsModule,
       ...sharedConfig.imports
    ],
    providers: [
        { provide: 'ORIGIN_URL', useValue: location.origin }
    ]
})
export class AppModule {
}

如果有人能指出我做错了什么，我将非常感激，但我找到的每一篇文章都表明，通过导入FormsModule可以解决这个问题。

Answer 1

您需要将formsmodule、reactiveformsmodule添加到app.module.shared.ts中

您的app.module.share.ts应该类似于。

import { NgModule } from '@angular/core';
import { RouterModule } from '@angular/router';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { AppComponent } from './components/app/app.component'
import { NavMenuComponent } from './components/navmenu/navmenu.component';
import { HomeComponent } from './components/home/home.component';
import { FetchDataComponent } from './components/fetchdata/fetchdata.component';
import { CounterComponent } from './components/counter/counter.component';
import { HelloWorldComponent } from './components/helloworld/helloworld.component';
import { WeatherComponent } from './components/weather/weather.component';

export const sharedConfig: NgModule = {
    bootstrap: [ AppComponent ],
    declarations: [
        AppComponent,
        NavMenuComponent,
        CounterComponent,
        FetchDataComponent,
        HomeComponent,
        HelloWorldComponent,
        WeatherComponent
    ],
    imports: [
        FormsModule,
        ReactiveFormsModule
        RouterModule.forRoot([
            { path: '', redirectTo: 'home', pathMatch: 'full' },
            { path: 'home', component: HomeComponent },
            { path: 'counter', component: CounterComponent },
            { path: 'fetch-data', component: FetchDataComponent },
            { path: 'hello', component: HelloWorldComponent },
            { path: 'weather', component: WeatherComponent },
            { path: '**', redirectTo: 'home' }
        ])
    ]
};