How to fix 400 Bad Request error?

Question

I'm getting a The remote server returned an error: (400) Bad Request error when trying to run my code. Any help would be appreciated. Thanks.

    // Open request and set post data
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create("myurl.com/restservice/Login");
    request.Method = "POST";
    request.ContentType = "application/json; charset:utf-8";
    string postData = "{ \"username\": \"testname\" },{ \"password\": \"testpass\" }";

    // Write postData to request url
    using (Stream s = request.GetRequestStream())
    {
        using (StreamWriter sw = new StreamWriter(s))
            sw.Write(postData);
    }

    // Get response and read it
    using (Stream s = request.GetResponse().GetResponseStream()) // error happens here
    {
        using (StreamReader sr = new StreamReader(s))
        {
            var jsonData = sr.ReadToEnd();
        }
    }

JSON EDIT

Changed to:

{ \"username\": \"jeff\", \"password\": \"welcome\" }

But still not working.

EDIT

This is what I found that works:

       // Open request and set post data
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create("myurl.com/restservice/Login");
    request.Method = "POST";
    request.ContentType = "application/json";
    string postData = "{ \"username\": \"testname\", \"password\": \"testpass\" }";

    // Set postData to byte type and set content length
    byte[] postBytes = System.Text.UTF8Encoding.UTF8.GetBytes(postData);
    request.ContentLength = postBytes.Length;

    // Write postBytes to request stream
    Stream s = request.GetRequestStream();
    s.Write(postBytes, 0, postBytes.Length);
    s.Close();

    // Get the reponse
    WebResponse response = request.GetResponse();

    // Status for debugging
    string ResponseStatus = (((HttpWebResponse)response).StatusDescription);

    // Get the content from server and read it from the stream
    s = response.GetResponseStream();
    StreamReader reader = new StreamReader(s);
    string responseFromServer = reader.ReadToEnd();

    // Clean up and close
    reader.Close();
    s.Close();
    response.Close();

Why are you mucking around with Streams? Use a [`WebClient`](http://msdn.microsoft.com/en-us/library/system.net.webclient.aspx) instead! — qJake, Apr 12 '12 at 20:40
WebClient is a good idea. But also, note that a 400 request usually denotes the server not understanding your request. A bad payload is the likely culprit, especially since you seem to have incorrect JSON. — yamen, Apr 12 '12 at 20:43

jorgehmv · Accepted Answer · 2012-04-12T20:46:59.327

5

can you try string postData = "[{ \"username\": \"testname\" },{ \"password\": \"testpass\" }]";

That way you are sending an array of 2 objects

Edit: Also maybe what you really want to send is just an object with 2 properties, then it would be string postData = "{ \"username\": \"testname\", \"password\": \"testpass\" }"

edited Apr 12 '12 at 20:46

answered Apr 12 '12 at 20:40

jorgehmv

3,633
3
25
39

3

Many REST services return a HTTP 400 if the data is invalid, such as Viamenete and Palletways – Apr 12 '12 at 20:42
Could the problem be the **postData**? It looks like it's sending the \ slashes literally. – Trey Copeland Apr 12 '12 at 20:51
I don't think that would be a problem they are just escape characters.. where are you seeing those slashes being sent? – jorgehmv Apr 12 '12 at 20:58
In debug mode when I hover over postData. – Trey Copeland Apr 12 '12 at 21:09
Ok, debug mode will show you escaped-strings, but you can be sure they are being sent without slashes. So changing the json string didnt work? – jorgehmv Apr 12 '12 at 21:13
Maybe I need another method of posting data & getting the response? – Trey Copeland Apr 12 '12 at 21:16
Maybe, try WebClient as @SpikeX recommended, i recommend you to use fiddler too http://www.fiddler2.com/fiddler2/ maybe you find a problem we are missing, if that doesn't work either then i would start looking for an issue in the server side – jorgehmv Apr 12 '12 at 21:25
I have fiddler open. I never see the http request to myurl.com/restservice/Login. I only see my initial page load. – Trey Copeland Apr 12 '12 at 21:35
@jorgehmv I posted my solution – Trey Copeland Apr 13 '12 at 14:52

score 0 · Answer 2 · answered Apr 12 '12 at 20:41

0

It looks as though it may be coming from the JSON you are posting as it is invalid, see below what you are sending but in a valid form:

{
    "username": "testname",
    "password": "testpass"
}

answered Apr 12 '12 at 20:41

As I said in my other comment, many REST services return a HTTP 400 if the data is invalid, such as Viamenete and Palletways. I have just today been working with a HTTP based web service that does this exact same thing. – Apr 12 '12 at 20:43

score 0 · Answer 3 · answered Apr 12 '12 at 20:42

0

postData is not a valid Json object

{ "username": "testname" },{ "password": "testpass" }

Try to use a Json parser like Json.Net, JavaScriptSerializer or DataContractJsonSerializer instead of forming it manually

answered Apr 12 '12 at 20:42

L.B

114,136
19
178
224

How to fix 400 Bad Request error?

3 Answers3

Linked