NG模型检查是否已输入相同的数据

Question

我有一个看起来像这样的表格

<form action="" method="post" class="form form--login">
                        <div class="form__field">
                          <label class="fontawesome-user" for="login__firstname"><span class="hidden">Name</span></label>
                          <input id="login__firstname" ng-model="emailInvite.forename" typ

e="text" class="form__input" placeholder="Name" required>
                        </div>
                        <div class="form__field">
                          <label class="fontawesome-user" for="login__surname"><span class="hidden">Surname</span></label>
                          <input id="login__surname" ng-model="emailInvite.surname" type="text" class="form__input" placeholder="Surname" required>
                        </div>
                        <div class="form__field">
                          <label class="fontawesome-envelope" for="login__email"><span class="hidden">Email</span></label>
                          <input id="login__email" ng-model="emailInvite.email" type="text" class="form__input" placeholder="Email" required>
                        </div>
                        <div class="form-group">
                          <p>Upload Emails here </p>
                         <input type="file" id="exampleInputFile">
                         <p class="help-block">Using .csv to upload</p>
                       </div>
                        <div class="form__field">
                          <input type="button" class="btn btn-info" ng-click="saveInvites()" value="Save Email">
                        </div>
                      </form>

目前它填充了一个数据库和一个列表，我想这样做，以便列表不填充是两次输入相同的detials。例如同样的电子邮件。

继承我的控制器表格

$scope.emailInvite = {
  forename: '',
  surname: '',
  email: ''
};

$scope.saveInvites = function (){
  var emailDetails = {
    forename: $scope.emailInvite.forename,
    surname: $scope.emailInvite.surname,
    email: $scope.emailInvite.email,
    event_id: $scope.eventId
  }

  $scope.emailInvites.push(emailDetails);

  var res = $http.post('/delegates.json', emailDetails);

  res.success(function (data, status, headers, config) {
      // $state.go('event.payments');
      bootbox.alert("Saved email details");
  });
  res.error(function (data, status, headers, config) {
      //TODO proper error needs fixes on server
      bootbox.alert("Email not saved: " + JSON.stringify({data: data}));
  });
};
});