Javascript 无法使用firebase数据填充下拉列表
我试图用我的firebase数据填充下拉列表。我使用的是angular 9.1.9。请帮忙 类别.服务.tsJavascript 无法使用firebase数据填充下拉列表,javascript,angular,firebase,firebase-realtime-database,angularfire2,Javascript,Angular,Firebase,Firebase Realtime Database,Angularfire2,我试图用我的firebase数据填充下拉列表。我使用的是angular 9.1.9。请帮忙 类别.服务.ts constructor(private db: AngularFireDatabase) { } getCategories() { return this.db.list('/categories', (ref) => ref.orderByChild('name')) .snapshotChanges() .pipe( ma
constructor(private db: AngularFireDatabase) { }
getCategories() {
return this.db.list('/categories', (ref) => ref.orderByChild('name'))
.snapshotChanges()
.pipe(
map((actions) => {
return actions.map((action) => ({
key: action.key,
val: action.payload.val(),
}));
})
);
}
product-form.component.html
<select [ngModel] id="category" class="form-control">
<option value=""></option>
<option *ngFor="let c of categories$ | async" [value]="c.key">
{{c.payload.val().name}}
</option>
</select>
{{c.val.name}
会有所帮助,因为您的val
对象已经包含payload.val()
,只需从中访问name
属性即可
export class ProductFormComponent implements OnInit {
categories$;
constructor(categoryService: CategoryService) {
this.categories$ = categoryService.getCategories();
}