AngularJS ng-repeat handle empty list case

问题:

I thought this would be a very common thing, but I couldn't find how to handle it in AngularJS. Let's say I have a list of events and want to output them with AngularJS, then that's pretty easy:

<ul>
    <li ng-repeat="event in events">{{event.title}}</li>
</ul>

But how do I handle the case when the list is empty? I want to have a message box in place where the list is with something like "No events" or similar. The only thing that would come close is the ng-switch with events.length (how do I check if empty when an object and not an array?), but is that really the only option I have?

回答1:

You can use ngShow.

<li ng-show="!events.length">No events</li>

See example.

Or you can use ngHide

<li ng-hide="events.length">No events</li>

See example.

For object you can test Object.keys.

回答2:

And if you want to use this with a filtered list here's a neat trick:

<ul>
    <li ng-repeat="item in filteredItems  = (items | filter:keyword)">
        ...
    </li>
</ul>
<div ng-hide="filteredItems.length">No items found</div>

回答3:

You might want to check out the angular-ui directive ui-if if you just want to remove the ul from the DOM when the list is empty:

<ul ui-if="!!events.length">
    <li ng-repeat="event in events">{{event.title}}</li>
</ul>

回答4:

With the newer versions of angularjs the correct answer to this question is to use ng-if:

<ul>
  <li ng-if="list.length === 0">( No items in this list yet! )</li>
  <li ng-repeat="item in list">{{ item }}</li>
</ul>

This solution will not flicker when the list is about to download either because the list has to be defined and with a length of 0 for the message to display.

Here is a plunker to show it in use: http://plnkr.co/edit/in7ha1wTlpuVgamiOblS?p=preview

Tip: You can also show a loading text or spinner:

  <li ng-if="!list">( Loading... )</li>

回答5:

<ul>
    <li ng-repeat="item in items | filter:keyword as filteredItems">
        ...
    </li>
    <li ng-if="filteredItems.length===0">
        No items found
    </li>
</ul>

This is similar to @Konrad 'ktoso' Malawski but slightly easier to remember.

Tested with Angular 1.4

回答6:

Here's a different approach using CSS instead of JavaScript/AngularJS.

CSS:

.emptymsg {
  display: list-item;
}

li + .emptymsg {
  display: none;
}

Markup:

<ul>
    <li ng-repeat="item in filteredItems"> ... </li>
    <li class="emptymsg">No items found</li>
</ul>

If the list is empty, <li ng-repeat="item in filteredItems">, etc. will get commented out and will become a comment instead of a li element.

回答7:

You can use this ng-switch:

<div ng-app ng-controller="friendsCtrl">
  <label>Search: </label><input ng-model="searchText" type="text">
  <div ng-init="filtered = (friends | filter:searchText)">
  <h3>'Found '{{(friends | filter:searchText).length}} friends</h3>
  <div ng-switch="(friends | filter:searchText).length">
    <span class="ng-empty" ng-switch-when="0">No friends</span>
    <table ng-switch-default>
      <thead>  
        <tr>
          <th>Name</th>
          <th>Phone</th>
        </tr>
      </thead>
      <tbody>
      <tr ng-repeat="friend in friends | filter:searchText">
        <td>{{friend.name}}</td>
        <td>{{friend.phone}}</td>
      </tr>
    </tbody>
  </table>
</div>

回答8:

i usually use ng-show

<li ng-show="variable.length"></li>

where variable you define for example

<div class="list-group-item" ng-repeat="product in store.products">
   <li ng-show="product.length">show something</li>
</div>

回答9:

you can use ng-if because this is not render in html page and you dont see your html tag in inspect...

<ul ng-repeat="item in items" ng-if="items.length > 0">
    <li>{{item}}<li>
</ul>
<div class="alert alert-info">there is no items!</div>