Suppose we're building an address book application (contrived example) with AngularJS.
We have a form for contacts that has inputs for email and phone number, and we want to require one or the other, but not both: We only want the email
input to be required if the phone
input is empty or invalid, and vice versa.
Angular has a required
directive, but it's not clear from the documentation how to use it in this case. So how can we conditionally require a form field? Write a custom directive?
There's no need to write a custom directive. Angular's documentation is good but not complete. In fact, there is a directive called ngRequired
, that takes an Angular expression.
<input type='email'
name='email'
ng-model='contact.email'
placeholder='[email protected]'
ng-required='!contact.phone' />
<input type='text'
ng-model='contact.phone'
placeholder='(xxx) xxx-xxxx'
ng-required='!contact.email' />
Here's a more complete example: http://jsfiddle.net/uptnx/1/