TypeScript Utility Types 是一組內建的型別工具，用於操作和組合現有型別，以產生新的型別。這些工具可以讓開發者更容易地處理和操作 TypeScript 型別，提高程式碼的可讀性和可維護性。
以下介紹幾個常用的 Utility Types：
Record<Keys, Type>
interface CatInfo {
age: number;
breed: string;
}
type CatName = 'miffy' | 'boris' | 'mordred';
const cats: Record<CatName, CatInfo> = {
miffy: { age: 10, breed: 'Persian' },
boris: { age: 5, breed: 'Maine Coon' },
mordred: { age: 16, breed: 'British Shorthair' }
}
|
廣告
Pick<Type, Keys>
參數選擇
interface Todo {
title: string;
description: string;
isCompleted: boolean;
}
type TodoPreview = Pick<Todo, 'title' | 'isCompleted'>
const todo: TodoPreview = {
title: 'title',
isCompleted: true
}
|
Omit<Type, Keys>
參數排除
interface Todo {
title: string;
description: string;
isCompleted: boolean;
createdAt: number;
}
type TodoPreview = Omit<Todo, 'description'>
const todo: TodoPreview = {
title: 'title',
isCompleted: true,
createdAt: 20230301
}
|
參考資源：
https://www.typescriptlang.org/docs/handbook/utility-types.html
https://www.youtube.com/watch?v=GinkGJZBHIY
廣告
評論