typescript

 

基础类型

 

let isDone: boolean = false;
let decLiteral: number = 6;
let name: string = "bob";

• 数组

let list: number[] = [1, 2, 3];
let list: Array<number> = [1, 2, 3];

 

函数类型

type in line

let add=function(x:number,y?:number):string{
    return 'asdfasdf'
}


let add1=(x:string,y?:string):number=>{
    return 21
}

　　

interface

interface Foo {
    (a: string | number, b: string | number): string | number
}
let foo: Foo = (a, b) => {
    return a + b
}

　　

type

type Foo = (a: string, b: string) => string
let foo: Foo = (a, b) => {
    return a + b
}
// or
type Foo = {
    (a: strin, b: string): string
}
let foo: Foo = (a, b) => {
    return a + b
}

　　

函数重载

interface Foo {
  (a: string, b: string): string
  (a: number, b: number): number
}

let foo1: Foo = (a, b) => {
  return a + b
}

　　

function foo(a: string | number, b: string | number): string | number {
    return a + b
}

let a = foo('a', 'b') // 'ab': string
let b = foo(0, 1)     // 1: number
let c = foo('a', 1)   // error: No overload matches this call.

　　

type interface 区别

•   type 可以声明基本类型别名，联合类型，元组等类型
• interface 能够声明自动合并