<body ng-app="ngRequiredExample">
<div ng-controller="ExampleController">
  <form name="form">
    <label for="required">Toggle required: </label>
    <input type="checkbox" ng-model="required" id="required" />
    <br>
    <label for="input">This input must be filled if `required` is true: </label>
    <input type="text" ng-model="model" id="input" name="input" ng-required="required" /><br>
    <hr>
    required error set? = <code>{{form.input.$error.required}}</code><br>
    model = <code>{{model}}</code>
  </form>
</div>
</body>
angular.module('ngRequiredExample', [])
  .controller('ExampleController', ['$scope', function($scope) {
    $scope.required = true;
  }]);

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. //cdnjs.cloudflare.com/ajax/libs/angular.js/1.5.2/angular.min.js