结构化存储数据

属性名称可以是数字、字符串，字符串可以不用引号包住

都会被自动转为字符串

var obj = {
  make: "Ford",
  5: "five",
  "model": "focus",
	'space s': 'looks cool'
};

Access object properties

var obj = {
	propertyName: 'lyly',
	'property name': 'lala'
}
obj.propertyName
obj['propertyName']
obj['property name']
var pName = 'property name'
obj[pName]

Add new properties

var obj = {
	name: 'man'
}
obj.lastName = 'last name'
obj.['first name'] = 'first name'

Delete Properties

delete obj.propertyName
delete obj['property name']

Check property exists（继承的属性返回false）

obj.hasOwnProperty("propertyName");// true or false