Angular ng-model-options - Debounce

less than 1 minute read

TIL about the ng-model-options directive, which augments the behavior of an input element bound to a scope property via ng-model.

I was looking for a way to put a short time-delay on a text input in our app. The delay would prevent the ng-model scope property bound to the text input from updating, until we were roughly sure that the user had finished typing. This delay will probably wind up being somewhere between 350 and 500ms, which is nearly imperceivable to the end user.

Enter the ng-model-options directive, particulary the debounce option. Debounce does exactly what I describe above: it waits a number of milliseconds before updating the scope property to which the input is bound.


	<input ng-model="" ng-model-options="{ debounce: 1000 }"></input>

When the user enters a username to the input above, $ will only update if no change is detected in the input field for 1000ms. This prevents any watchers / API calls that are reactive based on user input from needlessly firing when the user hasn’t finished inputting their full query yet.

The only remaining issue…ng-model-options was added in angular 1.3 and we are still on 1.2.27 at work…

I think we’re due for an upgrade!