Angular2解决订阅中的承诺？

Question

有没有办法让这个伪代码工作？

private letsSee(): Promise<any> {
  return new Promise(resolve => {
    this.someService.someValue.subscribe((nextValue) => {
      resolve(nextValue);
    });
  });
}

Answer 1

将Observable转换为Pormise：

private letsSee(): Promise<any> {
  return this.someService.someValue.toPromise();
}