将用户名和密码传递给Web API

Question

我有一个角度2方法：

version: '3.3'

services:
  fancyservice:
    restart: always
    image: fancyservice
  aat-runner:
    environment:
      - FancyServiceUrl=http://fancyservice/
      - COMPOSE_CONVERT_WINDOWS_PATHS=1
    volumes:
      - .:/output:rw
    restart: always
    image: aat-runner
    volumes:
      - aat-output:c:\aat-output\

volumes:
  aat-output:

一个ASP.Net Core方法，它接收HttpContext

login(usernameparam: string, passwordparam: string): Observable<boolean> {
    let headers = new Headers({
        'Content-Type': 'application/x-www-form-urlencoded', 'Accept-Charset': 'utf-16', 'Access-Control': 'Allow - Origin'
    });
    let options = new RequestOptions({ headers: headers });

    return this.http.post('http://localhost:64116/token',
        { username : usernameparam, password: passwordparam },
        options)
        .map((response: Response) => {
            // login successful if there's a jwt token in the response
            debugger;
            let token = response.json() && response.json().token;
            if (token) {
                this.token = token;

                localStorage.setItem('currentUser', JSON.stringify({ username: usernameparam, token: token }));
                return true;
            } else {
                return false;
            }
        });
}

然而，当我收到HttpContext时，用户名和密码都是空的。在查看来自浏览器的请求时，它明确指出，Form-Data包含这两个。我错过了什么？