lifecycledecorator.ts

const DESTROY = 'ngOnDestroy';

export function Lifecycle(name?: string): PropertyDecorator {
  return function(target, prop: string) {
    const namex = !name ? prop.slice(0, -1) : name;

    const handler = target[namex];
    const onDestroy = target[DESTROY];

    if (namex !== DESTROY) {
      Object.defineProperty(target, DESTROY, {
        configurable: true,
        enumerable: true,
        writable: true,
        value: function(change) {
          if (onDestroy) {
            onDestroy.call(this, change);
          }

          this[prop].complete();
        }
      });
    }

    Object.defineProperty(target, name, {
      configurable: true,
      enumerable: true,
      writable: true,
      value: function(change) {
        if (handler) {
          handler.call(this, change);
        }

        let p = this[prop];

        if (namex !== DESTROY) {
          p.next();
        } else {
          p.next();
          p.complete();
        }

      }

    });
  };

}