ASP.NET WEB API 我需要异步客户端

我有一个 Web API 应用程序，它公开了某些异步方法，例如：

public async Task<HttpResponseMessage> Put(string id){
  var data = await Request.Content.ReadAsStringAsync();
  //do something to put data in db
return Request.CreateResponse(HttpStatusCode.Ok);
}

我还有一个类库，它通过System.Net.WebRequest使用此API，如下所示：

   var request = (HttpWebRequest)WebRequest.Create(url);
   var response = await request.GetResponseAsync();

响应是否需要异步检索？如果是这样，为什么？或者我也可以使用request.GetResponse();.

我之前使用了GetResponse，它有时会抛出 500 错误 （ An asynchronous module or handler completed while an asynchronous operation was still pending ）。一旦我将其更改为GetResponseAsync()，我就不再收到此错误。

编辑：有时会引发 500 错误的代码

我将 web api 方法简化为（只是为了检查 500 错误是业务逻辑还是其他错误）。注意：这是在将消费者更改为异步之后（第一个函数是消费者，然后是 api 方法）：

    public HttpWebResponse(GetApiResponseForPut(string url, string putData, NameValueCollection headers)
    {
      var request = (HttpWebRequest)WebRequest.Create(url);
            request.CookieContainer = _cookieContainer;
            request.Method = "PUT";
            if (headers != null)
            {
                request.Headers.Add(headers);
            }
            var encoding = new ASCIIEncoding();
            var byte1 = new byte[0];
            if (putData != null)
            {
                byte1 = encoding.GetBytes(putData);
            }
            request.ContentType = "application/x-www-form-urlencoded";
            request.ContentLength = byte1.Length;

            Stream requestStream = request.GetRequestStream();
            requestStream.Write(byte1, 0, byte1.Length);
            requestStream.Close();
            var response = await request.GetResponseAsync();
            return (HttpWebResponse)response;
    }
    public async Task<HttpResponseMessage> Put(string id)
    {
      HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK);
      return response;
    }