Angular2 can bind css class as follows `[class.fa-train]="true"`, but can I bind them at runtime (something like `[class[key]]="true"`) ? For example, I have an array:
```javascript
['fa-train', 'fa-subway', 'fa-bed']
```
I would like to convert them as follows:
```javascript
<i class="fa fa-train"></i>
<i class="fa fa-subway"></i>
<i class="fa fa-bed"></i>
```
Thanks.