Dynamic form validation in angularJS not working

Issue

I have created dynamic form, And adding the ng-required attributes dynamically to my controls. but now it’s not working .

This is my JS :

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

    app.controller('main', function($scope){ 
      $scope.Control={};
     $scope.Attributes =[
   {
     "Name":"FirstName",
     "Required":true
   },
   {
     "Name":"LastName",
     "Required":false
   },
   {
     "Name":"Email",
     "Required":true
   },
   {
     "Name":"Age",
     "Required":false
   }];

        $scope.submitForm = function(isValid) {

            // check to make sure the form is completely valid
            if (isValid) { 
                alert('our form is amazing');
                alert($scope.Control[1]);  // to check correct index
            }else{
              return;
            }

        };
    });

And My HTML :

<html>

<head lang="en">

  <script src="//ajax.googleapis.com/ajax/libs/angularjs/1.3.8/angular.min.js"></script>
  <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.3/css/bootstrap.min.css" />
  <script src="app.js"></script>

</head>

<body ng-app="birthdayToDo" ng-controller="main">
  <form name="userForm" ng-submit="submitForm(userForm.$valid)" novalidate>
    <table>
      <tr ng-repeat="attribute in Attributes">
        <td>{{attribute.Name}}</td>
        <td>
          <input type="text" name="Control[$index]" ng-model="Control[$index]" ng-required="{{attribute.Required}}" />
        </td>
        <td>
         <p ng-show="userForm.Control[$index].$error.required">{{attribute.Required == "true" && attribute.Name+' Required' || ''}}</p>
        </td>
      </tr>
    </table>
    <input type="submit" value="Save" />
  </form>
</body>

Plunker Link

I want to show error message when either the textbox value change or form is submitted .

But when I’m doing same thing with static form it’s working.
working plunker

Solution

Dynamic control names and form validation does not work that well with older angular versions (< 1.3.x). And to add to that you have a very old angular version (1.0.3). If you upgrade to 1.3.x version of angular you could easily achieve this with some changes (some of them you need anyways):

1) As mentioned by @dfsq you need to provide a boolean value to ng-required bound scope property otherwise you will end up setting truthy “true”/”false” to the controls and it will make everything required.

2) Use ng-attr-name to provide interpolated dynamic names. It will automatically expand to name attribute.

3) With 1.3 form controller sets an $error.required property on a property with the same name as that of the control and there are some more special properties it populates. You can always track total number of required errors with form.$error.$required.length

4) Do not use index to set the ng-model, use the proper attribute name itself so that it is more readable and easy to manage.

5) You could also utilize one-time binding (::) to avoid unwanted watches, example field names, display names, required attributes which if they are non changing lists.

6) You can use form controller’s special properties to manage your validations and other behaviors and interactions as you need. Here is a sample demo which just utilized only a small subset of what form controller provides.

View:

<form name="userForm" ng-submit="submitForm(userForm.$valid)" novalidate>
    <table>
      <tr ng-repeat="attribute in Attributes">
        <td>{{::attribute.Name}}</td>
        <td>
          <input type="text" ng-attr-name="{{::attribute.Name}}" ng-model="Control[attribute.Name]" ng-required="::attribute.Required" />
        </td>
        <td>
          <p ng-if="userForm[attribute.Name].$error.required" class="error">{{attribute.Name }} Required</p>
        </td>
      </tr>
    </table>
    <input type="submit" value="Save" ng-disabled="userForm.$invalid"/>{{Control}}
  </form>

Controller:

 /* Set proper boolean values to Required*/
 $scope.Attributes = [{
    "Name": "FirstName",
    "Required": true
  }, {
    "Name": "LastName",
    "Required": false
  }, {
    "Name": "Email",
    "Required": true
  }, {
    "Name": "Age",
    "Required": false
  }];

  $scope.submitForm = function(isValid) {

    // check to make sure the form is completely valid
    if (isValid) {
     /*Now control will have proper property names with respective ngmodel names*/
      console.log($scope.Control); 
    } else {
      return;
    }

  };

Sample Demo

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

app.controller('main', function($scope) {

  $scope.Control = {};

  //Set boolean values to Required
  $scope.Attributes = [{
    "Name": "FirstName",
    "Required": true 
  }, {
    "Name": "LastName",
    "Required": false
  }, {
    "Name": "Email",
    "Required": true
  }, {
    "Name": "Age",
    "Required": false
  }];

  $scope.submitForm = function(isValid) {


    if (isValid) {
      alert('our form is amazing');
      console.log($scope.Control); /*Use Controle object which has proper property names to reflect respective ngModel*/
    } else {
      return;
    }

  };
});
.error {
  color: red;
}
input.ng-invalid {
  border: 2px solid red;
}
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.3.3/angular.min.js"></script>
<div ng-app="birthdayToDo" ng-controller="main">
  <form name="userForm" ng-submit="submitForm(userForm.$valid)" novalidate>
    <table>
      <tr ng-repeat="attribute in Attributes">
        <td>{{::attribute.Name}}</td>
        <td>
          <input type="text" ng-attr-name="{{::attribute.Name}}" ng-model="Control[attribute.Name]" ng-required="::attribute.Required" />
        </td>
        <td>
          <p ng-if="userForm[attribute.Name].$error.required" class="error">{{attribute.Name }} Required</p>
        </td>
      </tr>
    </table>
    <input type="submit" value="Save" ng-disabled="userForm.$invalid"/>{{Control}}
  </form>
</div>

Answered By – PSL

Answer Checked By – Katrina (AngularFixing Volunteer)

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