Angular学习:$q
$qcanbeusedintwofashions---onewhichismoresimilartoKrisKowal'sQorjQuery'sDeferredimplementations,andtheotherwhichresemblesES6promisestosomedegree.$q可以以两种方式使用---一种更类似于KrisKowal的Q或jQuery的Deferred实现,另一种在某种程度上类似于ES6的promises。$qconstructorThestreamlinedES6style