3.Object、object、{}

3.Object、object、{}

Object、object、{}等类型都不能定义null,undefined

1.Object包含所有类型（除null,undefined）

let a1:Object = 1
let a2:Object = '字符串'
let a3:Object = []
let a4:Object = {}
let a5:Object = ()=>{}
let a6:Object = true
let a7:Object = null //报错
let a8:Object = undefined // 报错

2.object包含引用类型

let a1:object = 1 //报错
let a2:object = '字符串' //报错
let a3:object = [] 
let a4:object = {}
let a5:object = ()=>{}
let a6:object = true //报错
let a7:object = null //报错
let a8:object = undefined // 报错

3.{} 相当于 new Object 包含所有类型（除null,undefined）

let a1:{} = 1
let a2:{} = '字符串'
let a3:{} = []
let a4:{} = {}
let a5:{} = ()=>{}
let a6:{} = true
let a7:{} = null //报错
let a8:{} = undefined // 报错
//使用了字面量{}类型无法对给对象进行操作
let obj:{} = {
    name:"fly"
}
obj.name = 'tom' //报错
obj.age = 18 //报错