(1) new features of the standard library
1. Meta-programming
① Getting and setting prototypes
--object.create ()
--object.getprototypeof ()
② managing property attributes with property descriptors
--object.defineproperty ()
--object.defineproperties ()
--object.create ()
--object.getownpropertydescriptor ()
③ List Properties
--object.keys ()
--object.getownpropertynames ()
④ protected objects
--object.preventextensions ()
--object.isextensible ()
--object.seal ()
--object.issealed ()
--object.freeze ()
--object.isfrozen ()
(2) New method
① New Method String.prototype.trim ()
② accessing characters by square brackets
③ New Array method
--array.isarray ()
--array.prototype.every ()
--array.prototype.some ()
--array.prototype.filter ()
--array.prototype.foreach ()
--array.prototype.indexof ()
--array.prototype.lastindexof ()
--array.prototype.map ()
--array.prototype.reduce ()
④ New Date method
--date.now ()
--date.prototype.toisostring ()
(3) JSON
JSON is supported.
--josn.parse ()
--josn.stringify ()
--some built-in objects have a special Tojson method:
Boolean.prototype.toJSON ()
Number.prototype.toJSON ()
String.prototype.toJSON ()
Date.prototype.toJSON ()
--ecmascript5 new features of the in-depth understanding of javascript