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Angular2 * ngIf,其值来自* ngFor中的Object

[英]Angular2 *ngIf with a value from Object inside *ngFor

Id like to use a *ngIf inside a *ngFor where my role value is defined for that element. 我想在* ngFor内使用* ngIf,其中为该元素定义了我的角色值。

My Template looks like that: 我的模板如下所示:

<li class="nav-item" *ngFor="let entry of naviEntries">
      <button *ngIf="{{entry.role}}" ...>{{entry.name}}</button>
</li>

And inside my Component: 在我的组件中:

enter code here`export class NaviComponent implements OnInit {
    naviEntries: NaviEntry[];
    visitor: boolean = true;
    user: boolean = false;
    admin: boolean = false;

    constructor() { ... }

    ngOnInit() {
        ...
        this.naviEntries.push({name: 'Home', link: '', role: 'visitor'});
        this.naviEntries.push({name: 'User', link: '/user', role: 'user'});
        this.naviEntries.push({name: 'Admin', link: '/admin', role: 'admin'});
        ...

Inside the ngOnInit function im checking for if User is logged in or user is an admin. 在ngOnInit函数中,im检查用户是否已登录或用户是管理员。

Now i'd like to check with *ngIf if the Object i pushed to NaviEntries is allowed to show at the Navi 现在我想用* ng检查是否允许我推送到NaviEntries的对象显示在Navi上

Can i use an Object Value as an Variable used in my Component?? 我可以使用对象值作为组件中使用的变量吗?

Excample: Excample:

NaviEntry => {name: 'Admin', link: '/admin', role: 'admin'} NaviEntry => {name: 'Admin', link: '/admin', role: 'admin'}

In my Component => admin: boolean = true; 在我的Component => admin中:boolean = true;

Template: 模板:

*ngIf="{{entry.role}}" => *ngIf="admin" => true => show item *ngIf="{{entry.role}}" => * ngIf =“ admin” => true =>显示项目

I think you need something like : 我认为您需要类似的东西:

*ngIf="(entry.role === 'admin' && admin) || (entry.role === 'visitor' && visitor) || (entry.role === 'user' && user)"

Please read : 请阅读 :

https://angular.io/api/common/NgIf https://angular.io/api/common/NgIf

As you are using it bit wrong way. 当您使用它时,方法有点错误。


Optimised way to do : 优化的方式:

// component side
roleAccess = {'admin' : false , 'user' : false , 'visitor' : true}

// template side
*ngIf="roleAccess[entry.role]"

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