Submit a form with angular directive

ngFormCommit.js

// usage:
// <form ng-form-commit action="/" name='payForm' method="post" target="_top">
//   <input type="hidden" name="currency_code" value="USD">
//   <button type='button' ng-click='save(payForm)'>buy</button>
// </form>

.directive("ngFormCommit", [function(){
  return {
      require:"form",
      link: function($scope, $el, $attr, $form) {
          $form.commit = function() {
              $el[0].submit();
          };
      }
  };
}]).controller("AwesomeCtrl", ["$scope", function($scope){
   $scope.save = function($form) {
     if ($form.$valid) {
         $form.commit();
     }
   };
}])