Typescript

let isDon :boolean = false;
let str :string = "Hello TS";
let num :number = 123;

//函数没有返回值
function sayHello() : void {
	console.log("hello");
}
//函数参数是number类型，返回值是number类型
function getTotal(one: number, two: number) : number{
	return one + two;
}
//函数传参是对象的话，这样定义类型
function add({one, two}:{one: number, two: number}): number{
	return one + two;
}
//表示这个方法永远执行不完
function forNever() : never {
	while( true ){
		console.log('print')
	}
}
//可选参数
function run3(name :string, age? :number) : string{
	if(age){
		return `我是${name},今年${age}岁.`
	}else{
		return `我是${name},年龄保密.`
	}
}
//剩余参数
function sunf(...d :number[]) :number{
	let s: number = 0;
	for(let i:number = 0;i < d.length; i++){
		s += d[i]
	}
	return s
}

const numberArr : number[] = [1, 2, 3];
const stringArr : string[] = ['1', '2', '3'];
const arr : (number | string)[] = [1, '3', 2];
//type alias 类别名
type Lady = {name: string, age: number};
//类的形式
class Madam {
	name: string;
	age: number;
}
const girls: Lady[] = [
	{name:'Lux', age: 18},
	{name:'Rax', age: 28},
]
const girls2: Madam[] = [
	{name:'Lux', age: 18},
	{name:'Rax', age: 28},
]