~~~ namespace a { interface Person { xx: string; yy: string } function enhancer(target: any) { target.prototype.xx = 'xx'; target.prototype.yy = 'yy'; } @enhancer class Person { constructor() { } } let p = new Person(); console.log(p.xx); console.log(p.yy); } //把类整个替换 namespace b { function enhancer() { return function (target: any) { return class extends Person { constructor(name: string, age: number) { super(name, age); } getAge() { console.log(this.age); } } } } @enhancer() class Person { public name: string = 'person'; public age: number = 10; constructor(name: string, age: number) { this.name = name, this.age = age } } let p = new Person('zhufeng', 10); p.name; } //属性装饰器 装饰属性 namespace c { //target如果装饰的是个普通属性的话，那么这个target指向类的原型 Person.prototype //target装饰的是一个类的属性static,那么这个target指定类的定义 function upperCase(target: any, propertyName: string) { let value = target[propertyName]; const getter = () => value; const setter = (newVal: string) => { value = newVal.toUpperCase(); } delete target[propertyName]; Object.defineProperty(target, propertyName, { get: getter, set: setter, enumerable: true, configurable: true }); } function propertyEnumerable(flag: boolean) { return function (target: any, methodName: string) { } } function methodEnumerable(flag: boolean) { return function (target: any, methodName: string, propertyDescriptor: PropertyDescriptor) { propertyDescriptor.enumerable = flag; } } function setAge(age: number) { return function (target: any, methodName: string, propertyDescriptor: PropertyDescriptor) { target.age = age; } } function toNumber(target: any, methodName: string, propertyDescriptor: PropertyDescriptor) { let oldMethod = propertyDescriptor.value; propertyDescriptor.value = function (...args: any[]) { args = args.map(item => parseFloat(item)); return oldMethod.apply(this, args); } } class Person { static age: number; @upperCase @propertyEnumerable(false) name: string = 'zhufeng' @methodEnumerable(true) getName() { console.log('getName'); } @setAge(100) static getAge() { } @toNumber sum(...args: any[]) { return args.reduce((accu, item) => accu + item, 0); } } let p = new Person(); p.name = 'jiagou'; console.log(p.name);//JIAGOU for (let attr in p) { console.log('attr=' + attr); } console.log(Person.age); console.log(p.sum(1, '2', '3')); } namespace d { interface Person { age: number } //Person.prototype login 1 function addAge(target: any, methodName: string, paramsIndex: number) { console.log(target, methodName, paramsIndex); target.age = 10; } //参数装饰 方法参数 class Person { login(username: string, @addAge password: string) { console.log(this.age, username, password); } } let p = new Person(); p.login('zhufeng', '123'); } namespace e { function Class1Decorator() { return function (target: any) { console.log("类1装饰器"); } } function Class2Decorator() { return function (target: any) { console.log("类2装饰器"); } } function MethodDecorator() { return function (target: any, methodName: string, descriptor: PropertyDescriptor) { console.log("方法装饰器"); } } function Param1Decorator() { return function (target: any, methodName: string, paramIndex: number) { console.log("参数1装饰器"); } } function Param2Decorator() { return function (target: any, methodName: string, paramIndex: number) { console.log("参数2装饰器"); } } function PropertyDecorator(name: string) { return function (target: any, propertyName: string) { console.log(name + "属性装饰器"); } } @Class1Decorator() @Class2Decorator() class Person { @MethodDecorator() greet(@Param1Decorator() p1: string, @Param2Decorator() p2: string) { } @PropertyDecorator('name') name: string = 'zhufeng'; @PropertyDecorator('age') age: number = 10; } } //属性方法先执行，谁先写先执行谁 //方法的时候，先参数再方法，而且 他们一定会在一起 //最后是类 //如果是同类型的，先执行后写的 ~~~