How to get specific Header value in a Http.GetAsync call

Question

User-2015242085 posted

Hi

How to get specific Header value in a Http.GetAsync call

public async void GetDetailsByKey(string Key)
{
            try
            {
                string URL = "https://website.com/";
                HttpClient Http = new HttpClient();
                HttpResponseMessage response = Http.GetAsync((URL + ("details/" + Key))).Result;
                string res = await response.Content.ReadAsStringAsync();
                var AllHeaders = response.Headers.ToString();
                jsonDetails = res.ToString()  + "<br/><br/>Headers: " + AllHeaders;
            }
            catch
            {
                jsonDetails = "Error!";
            }
}

I can get all the headers like:

var AllHeaders = response.Headers.ToString();

But how to get a single header like "Header Name"

Answer 1

User1724605321 posted

Hi Primillo,

Please refer to this thread : https://stackoverflow.com/questions/25439421/how-to-get-an-specific-header-value-from-the-httpresponsemessage 

HttpHeaders headers = response.Headers;
IEnumerable<string> values;
if (headers.TryGetValues("X-BB-SESSION", out values))
{
  string session = values.First();
}

You can check other available solutions in that thread . 

If your requirement is to get specific header ,you can loop Request.Headers , for example :

string headers = String.Empty;
foreach (var key in Request.Headers.AllKeys)
  headers += key + "=" + Request.Headers[key] + Environment.NewLine;

You can add if...else statement to get specific header key/name .

Best Regards,

Nan Yu

Answer 2

User-2015242085 posted

Hi Nan Yu

I already tried that and I get an error on the line:

string session = values.First();

I get ...  IEnumerable<string> does not contain a definition for "First"

And the second code sample don't work

Any other idea on how to get just a specific header from the headers collection?

Best Regards

Answer 3

User-2015242085 posted

THX Nan Yu

You were right!

I just was missing:

using System.Linq;

This code do the job!

HttpHeaders headers = response.Headers;
string session = "";
IEnumerable<string> values;
if (headers.TryGetValues("X-Error-Cause", out values))
{
    session = values.First();
}

Regards