如何在 angular2 中显示 ngFor 中的 1 个元素? [英] How to show 1 element in ngFor in angular2?

问题描述

我有一个简单的 ngFor 循环遍历数组.但是，我添加了一个条件，即当索引为 <5 继续添加标签.之后，我只想添加一个额外的标签，该标签将用于下拉列表来查看其余标签.但它不起作用.

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>

这里的特点是我不想向用户显示无限数量的标签，我想将它限制为只有 5 个标签，并在 5 个标签之后有一个按钮，用于显示下拉菜单剩余的标签.

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.

这可以在angular2中做到吗?

Is this possible to do in angular2?

如果有，请赐教.

推荐答案

<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

除了 <div>DropDown Button</div> 在第 5 项之后添加之外的所有内容，您可以使用:

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>

这篇关于如何在 angular2 中显示 ngFor 中的 1 个元素?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！