Object: String-to-value ing; self-contained attributes; inherited attributes
String, number, and Boolean value: they are not objects. When their attributes are referenced, JS will call new XXX () to convert them into objects. When the reference ends, the temporary object (wrapped object) will disappear. Attribute assignment is ignored. You can also display the packaging object. Typeof: object. No practical significance
Operate on objects through reference
VaR x = {Name: 'sfp'}; var y = x; X. Name = 'wj'; console. Log ('Y. Name: '+ Y. Name );
Attribute name: empty string
VaR x = {Name:'s ', '': 'sfp'}; For (var key in X) {If (Key ='') {console. log (Key + ':' + X [Key]); // note the value format }}
The property value allows getter or setter Functions
Each attribute has the property features: can be written before 5, can be enumerated (for in can be output), can be configured (delete, modify ).
Object Features: Prototype, class, extensible flag.
Built-in object, Host Object (htmlelement, also built-in), custom object, own attribute, inherit attribute.
Historical reasons: the attribute name is reserved and must be enclosed by quotation marks. The last comma must be added. The attribute name contains spaces, hyphens, and reserved words. quotation marks are required.
Rhino-6 objects