在async httpclient xml文件中下载

Question

我想以异步方式下载xml文件，让用户知道该文件正在下载，同时在应用程序中执行其他操作

public static async Task<string> GetRequestAsync(string url)
{            
   using (var httpClient = new HttpClient() { MaxResponseContentBufferSize = int.MaxValue })
   {
     HttpResponseMessage response = await httpClient.GetAsync(url);
     response.EnsureSuccessStatusCode();
     return await response.Content.ReadAsStringAsync();
   }
}

使用此命令无法成功运行