AngularJS - 动态创建表单复选框

Question

我正在使用ng-repeat创建多个复选框。如果使用表单验证选中任何一个复选框，如何验证此表单？

<div class="checkbox" ng-repeat="nereg in northeastRegion track by $index" ng-click="nereg.selected = !nereg.selected">
  <input type="checkbox" ng-checked="nereg.selected" >
  <label for="">{{nereg.title}}</label>
</div>

JS

$scope.northeastRegion = [{
        title: 'New England',
        selected: false
      },
      {
        title: 'New York Metro',
        selected: false
      },
      {
        title: 'Philly Tri-State',
        selected: false
      },
      {
        title: 'Upstate New York',
        selected: false
      },
      {
        title: 'Washignton',
        selected: false
      }
    ];