import React from 'react' // 使用electron的功能 // const electron = window.require('electron') // 使用remote const { BrowserWindow } = window.require("@electron/remote") export default function App() { const openNewWindow = () => { new BrowserWindow({ width:500, height:500 }) } retu...
dy: number, easing: Easing) { if (easing === "ease-in") { // ... } else if (easing === "ease-out") { } else if (easing === "ease-in-out") { } else { // error! should not pass null or undefined. } } } let button = new UIElement(); button.animate...
If a default-initialized parameter comes before a required parameter, users need to explicitly pass undefined to get the default initialized value. 代码语言:javascript 代码运行次数:0 运行 AI代码解释 function buildName(firstName: string, lastName = "Smith") { // ... } 2.1.4. Rest Parameters...
interface A { a: string;}interface B { b: string;}let a = { a:'1' };let b = {b:'1'};function extend<T, U>(first: T, second: U): T & U { let result = <T & U>{}; for (let id in first) { (<any>result)[id] = (<any>first)[id]; } fo...
functiondescribe(person:unknown):string{if(!isPerson(person)){thrownewError('`describe` requires you to pass a `Person`');}letname=person.name??'someone';return`${name}is${person.age}years old`;} 既然我们已经有了这个功能,我们可以将这里的person类型更新为Person来让 TypeScript 用户有更好的...
// If you want to start measuring performance in your app, pass a function // to log results (for example: reportWebVitals(console.log)) // or send to an analytics endpoint. Learn more: https://bit.ly/CRA-vitals reportWebVitals() ...
substr(1) } if (typeof value === 'number') { value * value } } function passAny (value: any) { value.substr(1) value * value } 相比较来说, Mixed 更加安全, any 存在的意义更多是为了兼容以前的旧代码. 总结 flow 的学习, 更多的是让我们能够在理解一些 vue、 react 第三方项目源码时...
eat:function(name:string){ return`eat${name}`; }, speak:(name:string) =>`speak${name}`, }; console.log(tom.eat('Jerry')); console.log(tom.speak('哈哈哈')); 需要注意的是,虽然eat、speak分别是用普通函数和箭头函数声明的,但是它们具体是什么样的函数...
let a: keys='name'//passlet b: keys='age'//passlet c: keys='test'// error 而如果我们想要将一个类型不统一的JSON修改为统一类型的JSON也可以使用这种方式: const obj ={ name:'Niko', age:18, birthday: new Date() } const infos: Record<keyof typeof obj, string> ={ ...
interface Bird { fly(); layEggs(); } interface Fish { swim(); layEggs(); } function getSmallPet(): Fish | Bird { // ... } let pet = getSmallPet(); pet.layEggs(); // okay pet.swim(); // errors 这里的联合类型可能有点复杂,但是你很容易就习惯了。如果一个值的类型是A | B...