ts笔记（三）

1.partial 

2readonly

3pick

4record

 

5泛型索引

 

 定义数组

interface myArrar<number> {

        [n:number]

}

6映射

 

 7 in keyof

 8T[P]

8

type Props = {
    a: number
    b: string
    c: boolean
}

type prop1 = Props['a' | 'b']

type prop2 = Props[keyof Props]

 9declear