adding ng-invalid class on input mismatch

Issue

Angular adds ng-invalid class automatically to email input field if it’s invalid, how’s it possible to have the class ng-invalid added to input#confirmEmail if it’s doesn’t match to input#email and remove if they match.

Basically I’m not required to show any messages in case of mismatch, just wanna highlight the input field through ng-invalid class and validate the form based on that.

<li>
    <label for="email">Email</label>
    <input type="email" id="email" name="email" ng-model="data.account.email" ng-required="">
</li>
<li>
    <label for="confirmEmail">Confirm Email</label>
    <input type="email" id="confirmEmail" name="confirmEmail" ng-model="data.account.confirmEmail">
</li>

Solution

Expanding my comment to answer. Here is a simple compare directive validation which can be used to in-validate the form and the inputs if it does not match the entered value. Making use of ngModelController’s (>= V1.3.x) $validators it becomes easy to handle it.

Directive will look like this:

.directive('comparewith', ['$parse', function($parse){
  return {
     require:'ngModel',
      link:function(scope, elm, attr, ngModel){
        //Can use $parse or also directly comparing with scope.$eval(attr.comparewith) will work as well
        var getter = $parse(attr.comparewith);

        ngModel.$validators.comparewith = function(val){
          return val === getter(scope);
        }
        scope.$watch(attr.comparewith, function(v, ov){
          if(v !== ov){
             ngModel.$validate();
          }
        });
      }
  }
}]);

and use it as:

<li>
    <label for="email">Email</label>
    <input type="email" id="email" name="email" 
          ng-model="data.account.email" required>
</li>
<li>
    <label for="confirmEmail">Confirm Email</label>
    <input type="text" id="confirmEmail" name="confirmEmail"
           comparewith="data.account.email" required 
           ng-model="data.account.confirmEmail">
</li>

Demo

var app = angular.module('plunker', []);

app.controller('MainCtrl', function($scope) {
  $scope.submit = function(form) {
    if (form.$invalid) {
      alert("oops password and confirm must match and must be valid");
    } else {
      alert("Äll good!!");
    }
  };
}).directive('comparewith', ['$parse', function($parse) {
  return {
    require: 'ngModel',
    link: function(scope, elm, attr, ngModel) {
      var getter = $parse(attr.comparewith);

      ngModel.$validators.comparewith = function(val) {
        return val === getter(scope);
      }
      
      scope.$watch(attr.comparewith, function(v, ov){
         if(v !== ov){
            ngModel.$validate();
         }
      });
    }
  }
}]);
/* Put your css in here */

form.ng-invalid {
  border: 1px solid red;
  box-sizing: border-box;
}
input.ng-invalid {
  border: 2px solid red;
  box-sizing: border-box;
}
<!DOCTYPE html>
<html ng-app="plunker">

<head>
  <meta charset="utf-8" />
  <title>AngularJS Plunker</title>
  <script>
    document.write('<base href="' + document.location + '" />');
  </script>
  <link rel="stylesheet" href="style.css" />
  <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
  <script src="app.js"></script>
</head>

<body ng-controller="MainCtrl">
  <form name="form" ng-submit="submit(form)" novalidate>
    <ul>
      <li>
        <label for="email">Email</label>
        <input type="email" id="email" name="email" ng-model="data.account.email" required>
      </li>
      <li>
        <label for="confirmEmail">Confirm Email</label>
        <input type="text" id="confirmEmail" name="confirmEmail" comparewith="data.account.email" required ng-model="data.account.confirmEmail">
      </li>
    </ul>
    <button>Submit</button>
  </form>
</body>

</html>

Answered By – PSL

Answer Checked By – Mary Flores (AngularFixing Volunteer)

Leave a Reply

Your email address will not be published.