当HttpWebRequest.GetResponse抛出WebException时，如何读取返回的自定义错误消息？

Question

我有一个NET.Core API和简单的测试方法：

public async Task<IActionResult> TestApi()
{
    try
    {
        throw new UnauthorizedAccessException("My custom error");

        return Ok();
    }
    catch (UnauthorizedAccessException ex)
    {
        return StatusCode(401,ex.Message);
    }
    catch (Exception ex)
    {
        throw;
    }

}

我需要从客户端检索消息，如下所示：

var request = WebRequest.Create($"{baseUrl}{url}") as HttpWebRequest;
request.Method = "POST";
request.ContentType = "application/json";
request.Expect = "application/json";
request.ContentLength = 0;

if (parameters != null)
{
    request.ContentLength = serializedObject.Length;
    using (var writer = new StreamWriter(request.GetRequestStream()))
    {
        writer.Write(serializedObject);
    }
}

var response = request.GetResponse() as HttpWebResponse;
var responseEncoding = Encoding.GetEncoding(response.CharacterSet);

using (var sr = new StreamReader(response.GetResponseStream(), responseEncoding))
{
    var result = sr.ReadToEnd();
    return JsonConvert.DeserializeObject<T>(result);
}

现在request.GetResponse() as HttpWebResponse返回给我：

The remote server returned an error: (401) Unauthorized.

而不是My custom error 。 有人能指出我正确的方向吗？

Answer 1

这是一个简化的示例，它会读取您的自定义消息。 您的消息将在响应流中返回。

try
{
    var response = request.GetResponse() as HttpWebResponse;
}
catch (WebException ex) // this exception is thrown because of the 401.
{
    var responseStream = ex.Response.GetResponseStream();
    using (var reader = new StreamReader(responseStream))
    {
        var message = reader.ReadToEnd();
    }
}

Answer 2

返回一个ActionResult

Task<ActionResult>

然后，您可以在UnauthorizedObjectResult中包装未经授权的错误

return Unauthorized(new UnauthorizedObjectResult(errorModel));