Parse a raw HTTP Response in C# to get the Status Code

Question

Is there a simple way to parse an HTTP Response string such as follows:

"HTTP/1.1 200 OK\r\nContent-Length: 1433\r\nContent-Type: text/html\r\nContent-Location: http://server/iisstart.htm\r\nLast-Modified: Fri, 21 Feb 2003 23:48:30 GMT\r\nAccept-Ranges: bytes\r\nETag: \"09b60bc3dac21:1ca9\"\r\nServer: Microsoft-IIS/6.0\r\nX-Po"

I would like to get the Status Code. I do not necessarily need to turn this in to an HttpResponse object, but that would be acceptable as well as just parsing out the Status Code. Would I be able to parse that into the HttpStatusCode enum?

I am using a sockets based approach and cannot change the way I am getting my response. I will only have this string to work with.

Answer 1

EDIT Taking into account " I am using a sockets based approach and cannot change the way I am getting my response. I will only have this string to work with ".

How about

  string response = "HTTP/1.1 200 OK\r\nContent-Length: 1433\r\nContent-Type: text/html\r\nContent-Location: http://server/iisstart.htm\r\nLast-Modified: Fri, 21 Feb 2003 23:48:30 GMT\r\nAccept-Ranges: bytes\r\nETag: \"09b60bc3dac21:1ca9\"\r\nServer: Microsoft-IIS/6.0\r\nX-Po";

  string code = response.Split(' ')[1];
  // int code = int.Parse(response.Split(' ')[1]);

I had originally suggested this:

  HttpWebRequest webRequest =(HttpWebRequest)WebRequest.Create("http://www.gooogle.com/");
  webRequest.AllowAutoRedirect = false;
  HttpWebResponse response = (HttpWebResponse)webRequest.GetResponse();
  int statuscode = (int)response.StatusCode)

Answer 2

HTTP is a pretty simple protocol, the following should get the status code out pretty reliably (updated to be a tad more robust):

int statusCodeStart = httpString.IndexOf(' ') + 1;
int statusCodeEnd = httpString.IndexOf(' ', statusCodeStart);

return httpString.Substring(statusCodeStart, statusCodeEnd - statusCodeStart);

If you really wanted to you could add a sanity check to make sure that the string starts with "HTTP", but then if you wanted robustness you could also just implement a HTTP parser.

To be honest this would probably do: :-)

httpString.Substring(9, 3);

Answer 3

If it's just a string could you not just use a regex to extract the status code?

Answer 4

This updates the marked answer to handle some corner cases:

    static HttpStatusCode? GetStatusCode(string response)
    {
        string rawCode = response.Split(' ').Skip(1).FirstOrDefault();

        if (!string.IsNullOrWhiteSpace(rawCode) && rawCode.Length > 2)
        {
            rawCode = rawCode.Substring(0, 3);

            int code;

            if (int.TryParse(rawCode, out code))
            {
                return (HttpStatusCode)code;
            }
        }

        return null;
    }

Answer 5

Either do what DD59 suggests or use a regular expression.

Answer 6

coz the format of the status code remains same u can probably use smthing like this.

var responseArray = Regex.Split(response, "\r\n");
 if(responseArray.Length)>0
 {
 var statusCode = (int)responseArray[0].split(' ')[1];
 }