Typescript

TypeScriptとは?

let aaa = "안녕하세요"

aaa = 3

let bbb:string = "반갑습니다"

タイプスクリプトは変数のデータ型を規定し、同じデータ型のみが再割り当てされます。

//문자타입
    let ccc : string
    ccc = "반가워!"

//숫자타입
    let ddd : number = 10
    ddd = 20

//불린타입
    let eee : boolean = true
    eee = false
    eee = "false"  //오해하기 쉽지만 ""이 있어 문자열이이다

配列でも使用できます。たとえば、次のようにします。

//배열타입
    let fff: number[] = [1,2,3,4,5,"안냥하세여"] //오류 발생
    let ggg: string[] = ["철수","영희","훈이",13] // 오류 발생
    let hhh: (number | string)[] = [1,2,3,4,5,"안냥하세여"]

オブジェクトタイプ

//객체타입
    interface IProfile{
        name: string
        age: string | number
        school: string
        hobby?: string
    }

    let profile : IProfile ={
        name: "철수",
        age: 8,
        school: "다람쥐초등학교"
    }
    profile.age = "8" 
    profile.school= 123 // school: string이므로 오류 발생

hobby?

関数のタイプ

//함수타입
    const add =(money1:number, money2:number, unit:string):string => {
        return money1 + money2 + unit
    }
    const result = add(1000,2000,"원")

tsとtsx