<form name="test_form" ng-controller="TestCtrl"><input type="checkbox" name="a" ng-model="a" id="check" ng-checking="say()"/><label for="check">{{ a }}</label></form>var app = angular.module('Demo',[]);app.directive('ngChecking',function(){var fun1 = function(element,attrs){return function(scope,iElement,iAttrs){scope.$watch('a',function(){if(iElement[0].checked){if(iAttrs['ngChecking']){   var fun = iAttrs['ngChecking'].match(//w+()/g);scope[fun[0]]();}}})}}return {compile:fun1,restrict:'AE'}})app.controller('TestCtrl',function($scope){$scope.say = function(){alert(123)}});angular.bootstrap(document,['Demo']);