在回调中使用异步 IIFE

Question

如何按照此示例在回调中使用异步 IIFE 以避免错误消息：Promise returned in function argument where a void return 预计 .

  signIn(email: string, password: string, course?: ICourse): Promise<void> {
    return new Promise<UserCredential>((resolve, reject) =>
      this.afAuth.signInWithEmailAndPassword(email, password).then(
        (res) => {
          resolve(res);
        },
        (error: { message: string }) => {
          reject(error);
          this.toastrService.warning('Something has gone wrong. Please try again.', 'Oops!');
          this.logger.debug('An error occurred during Email Sign In');
          this.logger.error(error.message);
        }
      )
    ).then(
      (result: UserCredential) => {
        if (course && result.user) {
          this.builderSignIn(course, result.user.uid);
        } else {
          if (result != null) {
            this.ngZone.run(() => {
              void this.router.navigate(['dashboard']);
            });
          }
        }
      },
      (error: { message: string }) => {
        this.toastrService.warning(error.message, 'Oops!');
      }
    );
  }

Answer 1

new Promise 执行器回调应该 return void，但是您传递的箭头函数具有隐式 return 值的简洁主体。您可以通过

轻松解决这个问题

return new Promise((resolve, reject) => {
//                                      ^
   … /*
})
^ */

但实际上你只是 shouldn't be using the Promise constructor！简直

signIn(email: string, password: string, course?: ICourse): Promise<void> {
  return this.afAuth.signInWithEmailAndPassword(email, password).then((result: UserCredential) => {
    if (course && result.user) {
      this.builderSignIn(course, result.user.uid);
    } else {
      if (result != null) {
        this.ngZone.run(() => {
          void this.router.navigate(['dashboard']);
        });
      }
    }
  }, (error: { message: string }) => {
    this.toastrService.warning('Something has gone wrong. Please try again.', 'Oops!');
    this.logger.debug('An error occurred during Email Sign In');
    this.logger.error(error.message);
    this.toastrService.warning(error.message, 'Oops!');
  });
}

在回调中使用异步 IIFE

Use an asynchronous IIFE inside the callback

javascript

typescript

eslint

angular