则attachEvent的参数为onclick加上on，第二个参数为handler，事件处理函数。
并在事件处理程序中遇到以下错误: HandlerCreateTodo：importReact,{MouseEvent}from'react';constCounter:...
handler: (n: Event) =>void) {/*...*/}//Unsound, but useful and commonlistenEvent(EventType.Mouse, (e: MouseEvent) => console.log(e.x + ',' +e.y));//Undesirable alternatives in presence of soundnesslistenEvent(EventType.Mouse, (e: Event) => console.log((<MouseEvent>e)...
e.target.value总是带红色的波浪线，提…e 是 Event 不是 Element
interface Event { timestamp: number } interface MouseEvent extends Event { pageX: string, pageY: string } function addEventListener(eventType: EventType, handler: (event: Event) => void){ } // MouseEvent可以赋值给event类型 addEventListener(EventType.MouseEvent, (event: MouseEvent) => { ...
enumEventType{Mouse,Keyboard}interfaceEvent{timestamp:number;}interfaceMouseEventextendsEvent{x:number;y:number}interfaceKeyEventextendsEvent{keyCode:number}functionlistenEvent(eventType:EventType,handler:(n:Event)=>void){/* ... */}// Unsound, but useful and commonlistenEvent(EventType.Mouse,(e:Mo...
TypeScript 使用 structual typing,并在执行时类型擦除。 根据它的自身定位及他要服务的 JavaScript,Ts 被设计为了一个“不那么安全”的类型系统。 TypeScript 会帮助我们在开发中发现一些错误,但不是全部; Ty…
interface Event { timestamp: number; } interface MouseE extends Event { x: number; y: number } interface KeyE extends Event { keyCode: number } function listenEvent(eventType: EventType, handler: (n: Event) => void) { /* ... */ ...
EventHandler类型实现源码node_modules/@types/react/index.d.ts。 typeEventHandler<EextendsSyntheticEvent<any>>={ bivarianceHack(event:E): void }["bivarianceHack"]; typeReactEventHandler<T=Element>=EventHandler<SyntheticEvent<T>>; typeClipboardEventHandler<T=Element>=EventHandler<ClipboardEvent<T>>...
= Map<EventType, EventHandlerList | WildCardEventHandlerList>;export interface Emitter { all: EventHandlerMap; on<T = any>(type: EventType, handler: Handler<T>): void; on(type: '*', handler: WildcardHandler): void; off<T = any>(type: EventType, handler: Handler<T>): void...