TS 函数解析

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函数传参:

//let myAdd: (baseValue:number, increment:number) => number = function(x: number, y: number): number { return x + y; };

enum EventType { Mouse, Keyboard }

interface Event {
    timestamp: number;
}
interface MouseEvent extends Event {
    x1: number;
    y1: number;
}
interface KeyEvent extends Event {
    keyCode: number
}
function listenEvent(eventType: EventType, handler: (nnnnnnnnnn: Event) => string) {
    handler(null);
    return null;
}
function listenEvent1(eventType: EventType, handler: (nnnnnnnnnn: string) => string) {
    handler(null);
    return null;
}
function listenEvent2(eventType: EventType, handler: (nnnnnnnnnn: Event) => void) {
    handler(null);
    return null;
}
function  f(x:string){//(从js来看)声明定义了一个函数
    return "vvv";
}
function ff(x:string):string{//声明了一个函数,
    return "vvv";
}
var f1 = (x:string) => { //声明定义了一个函数
    return x;
}
var f11 : (x:string) => string;  //函数类型

var f111 = (x:string) => { //声明定义了一个函数
    return (x) => {return x}
}
var f2 = () => {  //声明定义了一个函数
    console.log("1223");
    return "sss";
}
var f22 = () => null;

listenEvent1( EventType.Keyboard, f111("sss")  ); //f111("sss") 使用的是返回值
//() => {console.log("1223");console.log("4456");return "1111";}  是定义了一个函数,传的是函数的定义,函数调用的时候才会传真实参数,
listenEvent(EventType.Keyboard, (e: MouseEvent) => {console.log("1223");console.log("4456");return "1111";}     );

listenEvent2(EventType.Keyboard, (e: MouseEvent) => null    );

listenEvent(EventType.Mouse, <(e: Event) => null> (  (e: MouseEvent,s:number) => console.log('e.x' + ',' + 'e.y') )  );
-------------------js 解析 ----------
//let myAdd: (baseValue:number, increment:number) => number = function(x: number, y: number): number { return x + y; };
var EventType;
(function (EventType) {
    EventType[EventType["Mouse"] = 0] = "Mouse";
    EventType[EventType["Keyboard"] = 1] = "Keyboard";
})(EventType || (EventType = {}));
function listenEvent(eventType, handler) {
    handler(null);
    return null;
}
function listenEvent1(eventType, handler) {
    handler(null);
    return null;
}
function listenEvent2(eventType, handler) {
    handler(null);
    return null;
}
function f(x) {
    return "vvv";
}
function ff(x) {
    return "vvv";
}
var f1 = function (x) {
    return x;
};
var f11; //函数类型
var f111 = function (x) {
    return function (x) { return x; };
};
var f2 = function () {
    console.log("1223");
    return "sss";
};
var f22 = function () { return null; };
listenEvent1(EventType.Keyboard, f111("sss")); //f111("sss") 使用的是返回值
//() => {console.log("1223");console.log("4456");return "1111";}  是定义了一个函数,传的是函数的定义,函数调用的时候才会传真实参数,
listenEvent(EventType.Keyboard, function (e) { console.log("1223"); console.log("4456"); return "1111"; });
listenEvent2(EventType.Keyboard, function (e) { return null; });
listenEvent(EventType.Mouse, (function (e, s) { return console.log('e.x' + ',' + 'e.y'); }));
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原文地址:https://www.cnblogs.com/yaowen/p/7217603.html