装饰器初探

{
    "compilerOptions": {
        "experimentalDecorators": true
    }
}

function classDecorator<T extends { new(...args: any[]): {} }>(constructor: T) {
  return class extends constructor {
    newProperty = "new property";
    hello = "override";
  }
}

function post(method: string, params: Record<string, any>) {
  return (target: any, key: any) => {
    const oldFn = target[key];
    target[key] = (...args: any[]) => {
      console.log(‘---before call---‘);
      oldFn.apply(target, args.concat(method, params))
      console.log(‘---after call---‘);
    }
  }
}

@classDecorator
class Greeter {
  property = "property";
  hello: string;
  constructor(m: string) {
    this.hello = m;
  }

  @post(‘/add‘, { name: ‘tian‘, age: 23 })
  say(...arg: any[]) {
    console.log(...arg);
  }
}

const greeter = new Greeter("world");
greeter.say(1111);
console.log(greeter);