typescript语法讲解

阿芯爱编程2025-01-13 22:29

typescript

1.let/const

typescript 复制代码

let msg:string='hello'  
let age:number=11  
let isDone:boolean=true

2.数据类型

typescript 复制代码

string  
number  
boolean  
any  
void  
null  
undefined  
never  
object  
array  
tuple  
enum

3.interface

typescript 复制代码

interface Person{  
name:string;  
age:number;  
sex?:string;  
readonly school:string;  
greet():void;  
[prop:string]:string;  
}  
let person:Person={name:'ivan',age:30}

4.联合类型与交叉类型

typescript 复制代码

let v:string|number=12  
type Admin=Employee&Manager

5.泛型

typescript 复制代码

function ide<T>(arg:T):T{  
return arg  
}  
let out=ide<number>(12)

6.类型别名

typescript 复制代码

type UserId=string  
let id:UserId='test11'

7.类型断言

typescript 复制代码

let v:any='test'  
let d:number=(<string>v).length  
let c:number=(v as string).length

8.装饰器

typescript 复制代码

function log(value:any,constructor:any){  
console.log(`${constructor.name}`)  
}  
@log  
class Student{  
constructor(){  
console.log('constructor')  
}  
}  
const s=new Student()