[ts]对象类型

官网地址

对象类型

匿名

function greet(person: { name: string; age: number }) {
    return "Hello " + person.name;
}

接口

interface Person {
    name: string;
    age: number;
}

function greet(person: Person) {
    return "Hello " + person.name;
}

类型别名

type Person = {
    name: string;
    age: number;
};

function greet(person: Person) {
    return "Hello " + person.name;
}

属性修饰

可选

interface PaintOptions {
    shape: Shape;
    // 属性可选
    xPos?: number;
}

只读

interface SomeType {
    readonly prop: string;
}

索引签名

interface StringArray {
    [index: number]: string;
}

interface NumberOrStringDictionary {
    [index: string]: number | string;
    length: number; // ok, length is a number
    name: string; // ok, name is a string
}

扩展类型

interface Colorful {
    color: string;
}

interface Circle {
    radius: number;
}

interface ColorfulCircle extends Colorful, Circle {}

交叉类型

interface Colorful {
    color: string;
}

interface Circle {
    radius: number;
}

type ColorfulCircle = Colorful & Circle;

泛型对象类型

interface Box<Type> {
    contents: Type;
}

type Box<Type> = {
    contents: Type;
}

type OrNull<Type> = Type | null;
type OneOrMany<Type> = Type | Type[];
type OneOrManyOrNull<Type> = OrNull<OneOrMany<Type>>;
type OneOrManyOrNull<Type> = OneOrMany<Type> | null
type OneOrManyOrNullStrings = OneOrManyOrNull<string>;

数组类型

interface Array<Type> {
    length: number;
    pop(): Type | undefined;
    push(...items: Type[]): number;
    // ...
}

ReadonlyArray

const roArray: ReadonlyArray<string> = ["red", "green", "blue"];

let x: readonly string[] = [];

元组类型

type StringNumberPair = [string, number];

// 可以包含剩余元素
type StringNumberBooleans = [string, number, ...boolean[]];
type StringBooleansNumber = [string, ...boolean[], number];
type BooleansStringNumber = [...boolean[], string, number];

// readonly
type ReadonlyStringNumberPair = readonly [string, number]