Typescript类型体操 - Pick
题目要求
实现 TS 内置的 Pick<T, K>
,但不可以使用它。
从类型 T
中选择出属性 K
,构造成一个新的类型。
例如:
interface Todo {
title: string
description: string
completed: boolean
}
type TodoPreview = MyPick<Todo, 'title' | 'completed'>
const todo: TodoPreview = {
title: 'Clean room',
completed: false,
}
English - Subject
Implement the built-in Pick<T, K>
generic without using it.
Constructs a type by picking the set of properties K
from T
For example:
interface Todo {
title: string
description: string
completed: boolean
}
type TodoPreview = MyPick<Todo, 'title' | 'completed'>
const todo: TodoPreview = {
title: 'Clean room',
completed: false,
}
答案
type MyPick<T extends {}, K extends keyof T> = { [P in K]: T[P] };