AngularJS Form Validation

<div ng-app="validationApp" ng-controller="mainController">

<div class="container">

<div class="row">  

<div class="col-sm-6">

    <!-- FORM ============ -->

    <form name="userForm" ng-submit="submitForm()" novalidate>

​

        <!-- USERNAME -->

      <div ng-form="forminside" ng-repeat =" item in passengerCount"> 

        <div class="form-group"  ng-class="{ 'has-error' : item.token.username.$invalid && !item.token.username.$pristine }">

            <label>Username</label>

            <input type="text" name="username" class="form-control" ng-model="item.token.username" ng-minlength="3" ng-maxlength="8">

            <p ng-show="item.token.username.$error.minlength" class="help-block">Username is too short.</p>

            <p ng-show="item.token.username.$error.maxlength" class="help-block">Username is too long.</p>

        </div>

      </div>

        <button type="submit" class="btn btn-primary" ng-disabled="userForm.forminside.$invalid">Submit</button>

    </form>

  </div>

​

</div>

</div>

</div>