Angular ng-class不起作用

Question

I've got the following HTML, and I'm trying to print a class using ng-class to the box, but it doesn't seem to work. What am I doing wrong?

http://plnkr.co/edit/5KqnetMmq5DPe1Dm2ecc?p=preview

   <div ng-controller="myObject">
        <a href="javascript:void(0)" ng-click="updateClass()">{{ type ? 'One' : 'Two' }}</a>

        <div class="box" ng-class="{{ type ? 'one' : 'two' }}"></div>
    </div>

Answer 1

ng-class gets evaluated on it's own. You don't need the {{}}

<div class="box" ng-class=" type ? 'one' : 'two' "></div>

Answer 2

ng-class as an attribute :

ng-class="expression"

ng-class as css :

class="ng-class: expression;"

You don't need to write expression in ng-class for more details you should go through ngClass