Built-in Helpers

Built-in Helpers

In the last section you learned how to write a helper. A helper is usually a simple function that can be used in any template. Ember comes with a few helpers that can make developing your templates a bit easier. These helpers can allow you to be more dynamic in passing data to another helper or component.

Using a helper to get a property dynamically

The {{get}} helper makes it easy to dynamically send the value of a variable to another helper or component. This can be useful if you want to output one of several values based on the result of a computed property.

{{get address part}}

if the part computed property returns "zip", this will display the result of this.get('address.zip'). If it returns "city", you get this.get('address.city').

Nesting built-in helpers

In the last section it was discussed that helpers can be nested. This can be combined with these sorts of dynamic helpers. For example, the {{concat}} helper makes it easy to dynamically send a number of parameters to a component or helper as a single parameter in the format of a concatenated string.

{{get "foo" (concat "item" index)}}

This will display the result of this.get('foo.item1') when index is 1, and this.get('foo.item2') when index is 2, etc.