下面是使用纳克级指令两种不同的方式。我需要他们两个，在相同的元素，但不起作用。

Here are 2 different ways to use the ng-class directive. I need them both, on the same element, but that doesn't work.

http://plnkr.co/edit/uZNK7I?p=$p$pview

<div ng-repeat="item in [1, 2, 3, 4, 5]" 
     ng-class="{ first: $first, last: $last }">{{item}}</div>

正确导致

<div class="first">1</div>
<div>2</div>
<div>3</div>
<div>4</div>
<div class="last">5</div>

在纳克级使用EX pression

http://plnkr.co/edit/tp6lgR?p=$p$pview

<div ng-repeat="item in [1, 2, 3, 4, 5]" 
     ng-class=" 'count-' + ($index + 1) ">{{item}}</div>

正确导致

<div class="count-1">1</div>
<div class="count-2">2</div>
<div class="count-3">3</div>
<div class="count-4">4</div>
<div class="count-5">5</div>

现在，如何一起使用它们？

我需要动态类的名称（如'count-'+ N ），但还需要多个类对象的语法。

Now, how about use them together?

I need dynamic class names (like 'count-' + n), but also need the object syntax for multiple classes.

我不能只用2 纳克级属性（的 http://plnkr.co/edit/OLaYke?p=$p$pview ），只有第一个作品。

I can't just use 2 ng-class attributes (http://plnkr.co/edit/OLaYke?p=preview), only the first one works.

有什么建议？