How to show 1 element in ngFor in angular2?

问题

I have a simple ngFor that loops through an array. However, I've added a condition that while the index is < 5 keep add the tag. and After that, I want to add an extra tag just once that will be used a dropdown to view the rest of the tags. But it doesn't work.

<li *ngFor="let tag of module.Tags; let i = index">
  <a *ngIf="i<5" href="#" class="span-tag tag">{{ tag }}</a>
  <div *ngIf="module.Tags.length > 5 && i == 6">DropDown Button</div>
</li>

The feature here is that I don't want to show unlimited number of tags to the user, I want to limit it to only 5 tags, and have a button after 5 tags which will be used to show the dropdown with the remaining tags.

Is this possible to do in angular2?

If so, please enlighten me.

回答1:

<li *ngFor="let tag of module.Tags | slice:0:5; let last=last">
  <a href="#" class="span-tag tag">{{ tag }}</a>
  <div *ngIf="last">DropDown Button</div>
</li>

https://angular.io/docs/ts/latest/api/common/index/SlicePipe-pipe.html

To get all added but the <div>DropDown Button</div> added after the 5th item you can use:

show = 5;

<li *ngFor="let tag of module.Tags|slice:0:show let i=index">
  <a href="#" class="span-tag tag">{{ tag }}</a>
  <div *ngIf="i==4 && show == 5" (click)="show = module.Tags.length">DropDown Button</div>
</li>

来源：https://stackoverflow.com/questions/42458664/how-to-show-1-element-in-ngfor-in-angular2

标签

arrays

angular