AngularJS $ on - 重新订阅未订阅的广播

Question

要从$broadcast中的$on取消订阅，可以执行

var cleanUp = $rootScope.$on('myBroadcast', function(){ ... });
cleanUp();

调用cleanUp()后，有没有办法重新订阅？

Answer 1

function foo () {
  return $rootScope.$on('myBroadcast', function(){ ... });
}
var cleanup = foo(); // listen

// somewhere down the road
cleanup(); // unlisten

// somewhere down the road
foo(); // listen again