运行时错误 this.object.remove 不是函数 [英] Runtime Error this.object.remove is not a function
问题描述
在我的 Ionic 应用程序中,我无法删除特定的键,它一直告诉我删除不是一个函数.在 angularfire2
上次更新之后,似乎有些事情发生了变化.它给了我这个错误:
In my Ionic app, I can't delete specific key, it keeps telling me that remove is not a function. It seems there are some things changed after the last updates in angularfire2
. It gives me this error:
Runtime Error
this.employees.remove is not a function
TypeError: this.employees.remove is not a function
at EmployeesPage.webpackJsonp.76.EmployeesPage.deleteEmployee (http://localhost:8100/build/main.js:319:24)
at Object.eval [as handleEvent] (ng:///AppModule/EmployeesPage.ngfactory.js:47:31)
at handleEvent (http://localhost:8100/build/vendor.js:12380:138)
at callWithDebugContext (http://localhost:8100/build/vendor.js:13850:42)
at Object.debugHandleEvent [as handleEvent] (http://localhost:8100/build/vendor.js:13438:12)
at dispatchEvent (http://localhost:8100/build/vendor.js:8972:21)
at http://localhost:8100/build/vendor.js:9583:20
at HTMLButtonElement.<anonymous> (http://localhost:8100/build/vendor.js:37400:53)
at t.invokeTask (http://localhost:8100/build/polyfills.js:3:15040)
at Object.onInvokeTask (http://localhost:8100/build/vendor.js:4238:33)
我也无法从我的 firebase 数据库中检索密钥.
I also unable to retrieve the key from my firebase database.
HTML 代码:
<ion-list>
<ion-item-sliding *ngFor="let employee of employees | async">
<ion-item>
<ion-avatar item-start>
<img src="../../assets/imgs/avatar.png">
</ion-avatar>
<h2>{{ employee.fname }} {{ employee.lname }}</h2>
<p>{{ employee.position }} at {{ employee.company }}</p>
<p>Key: {{ employee.key }}</p>
</ion-item>
<ion-item-options side="left">
<button ion-button color="secondary">
<ion-icon name="create"></ion-icon>
Edit
</button>
<button ion-button color="danger" (click)="deleteEmployee(employee.key)">
<ion-icon name="trash"></ion-icon>
Delete
</button>
</ion-item-options>
<ion-item-options side="right">
<button ion-button color="primary">
<ion-icon name="eye"></ion-icon>
View
</button>
</ion-item-options>
</ion-item-sliding>
打字稿代码:
import { Component } from '@angular/core';
import { IonicPage, NavController, NavParams } from 'ionic-angular';
import { AngularFireModule } from 'angularfire2';
import { AngularFireDatabase, AngularFireList } from 'angularfire2/database';
import { Observable } from 'rxjs/Observable';
@IonicPage()
@Component({
selector: 'page-employees',
templateUrl: 'employees.html',
})
export class EmployeesPage {
public employees: AngularFireList<any[]>;
constructor(
public navCtrl : NavController,
public navParams : NavParams,
public empDb : AngularFireDatabase
)
{
this.employees = this.empDb.list('/emloyeesionic').valueChanges();
}
deleteEmployee(key: string)
{
this.employees.remove(key);
}
}
我不知道是什么问题!!!!
I can't figure what the problem is!!!!
推荐答案
问题是你的 this.employees
在调用 valueChanges()
后不是对实时数据库的引用code> 但它是列表数据的 Observable.有一个单独的变量指向引用.如果您需要密钥,请使用 snapShotChanges()
Issue is your this.employees
is not a reference to the real-time database after calling valueChanges()
but is an Observable of the list data. Have a separate variable pointing to the reference. If you want the key, use snapShotChanges()
empRef:any;//the reference
constructor(
public navCtrl : NavController,
public navParams : NavParams,
public empDb : AngularFireDatabase
)
{
this.empRef = this.empDb.list('/emloyeesionic');
this.employees = this.empRef.snapshotChanges();
}
在 deleteEmployee 函数中,使用引用从列表中删除项目.
In deleteEmployee function, use the reference to delete the item from the list.
deleteEmployee(key: string)
{
this.empRef.remove(key);
}
在您的 HTML 中,您将在 employee.payload.val()
中获得实际值并键入 employee.payload.key
In your HTML, you will get actual value in employee.payload.val()
and key in employee.payload.key
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