如何从Request.CreateErrorResponse中读取错误消息？

Question

My WebAPI method returns an error response:

return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, "Something bad happened");

On my client end (an MVC project), I want to display the error message, but unable to get the message "Something bad happened" to display:

var response = await client.SendAsync(request);
if (!response.IsSuccessStatusCode)
{
    ViewBag.Error= response.ReasonPhrase; 
}

Other than ReasonPhrase, I've tried response.ToString() , response.Content.ToString() , and response.Content.ReadAsStringAsync() . None of them get me the message. How come Postman is able to display the message?

Any ideas how I can access the message string?

Answer 1

If your response content comes back as application/json , you can deserialize it with Json.Net like this:

if(!response.IsSuccessStatusCode)
{
    var errors = Newtonsoft.Json.JsonConvert.DeserializeObject<Dictionary<string, object>>(response.Content.ReadAsStringAsync().Result);
    var message = errors[HttpErrorKeys.MessageKey];

    // message is "Something bad happened"
}

Answer 2

I think response.Content.ReadAsStringAsync() returns a Task<string> , not a string . You'd need to use

response.Content.ReadAsStringAsync().Result 

or if your method is marked async you can await it.

string message = await response.Content.ReadAsStringAsync();

Answer 3

That's what I do to get error message. when you complete your debug, you can change return type

       public string someRequest()
    {
        try
        {
            var response = await client.SendAsync(request);
            return "Ok";
        }
        catch (Exception e)
        {
         return e.Message;
        }
    }