HttpClient for Windows Phone 8

Question

Hi,

I am converting a Windows 8 store application (WinRT, C#, XAML) to Windows Phone 8.

I am trying to use a routine from my Windows 8 application to send HTTP Client Request:

        public async Task SendHttpClientRequest( Uri uri )
            {
            try
                {
                HttpClient client = new HttpClient();
                HttpResponseMessage response = await client.GetAsync( uri );
                response.EnsureSuccessStatusCode();
                string responseBody = string.Empty;
                responseBody = await response.Content.ReadAsStringAsync();
                }
            catch ( HttpRequestException e )
                {
                Debug.WriteLine( "\nException Message :{0} ", e.Message );
                }
            }

However when using this code in Windows Phone 8 application, VS2012 does not recognize the HttpClient. According to the documentation the assembly should be System.Net.Http.dll however defining:

using System.Net.Http;

is not defined and creates error.

In the project References, I am using ".NET for Windows Phone" and "Windows Phone".

When searching for HttpClient in the Online Help:

http://social.msdn.microsoft.com/Search/en-US/windowsphone?query=httpclient&Refinement=184&ac=1

The links in the above web page lead to Windows 8 store application examples?!

What am I missing here?

Thanks,
EitanB

Answer 1

You should be using HttpWebRequest for the windows phone

http://msdn.microsoft.com/en-us/library/system.net.httpwebrequest.aspx

Answer 2

Hi,

Microsoft has what they call a

Portable HttpClient for .NET Framework and Windows Phone

The last version of it was published on 2/18/2013 and it should be included in the project using the NuGet package manager.

The following link describes it:

http://blogs.msdn.com/b/bclteam/archive/2013/02/18/portable-httpclient-for-net-framework-and-windows-phone.aspx

Installed it and

using System.Net.Http;

Is now recognized.

Thanks
EitanB

Answer 3

Hi Ken,

Just for my knowledge, how would you convert the function above to use HttpWebRequest?

From reading about HttpWebRequest I understand that I have to specify a callback function to handle the data returned?

Thanks,
EitanB

Answer 4

Got it to work with HttpWebRequest.

Apparently the portable HttpClient is not "there" yet (It was crushing sometimes on the Phone).

The new code is:

        private SynchronizationContext _context;
        public event EventHandler<ErrorEventArgs> Error;

        public void SendHttpClientRequest( Uri uri, string username, string password )
            {
            try
                {
                HttpWebRequest.RegisterPrefix( "http://", WebRequestCreator.ClientHttp );
                HttpWebRequest httpWebRequest = (HttpWebRequest)HttpWebRequest.Create( uri );
                if ( !string.IsNullOrEmpty( username ) || !string.IsNullOrEmpty( password ) )
                    {
                    httpWebRequest.Credentials = new NetworkCredential( username, password );
                    }

                // start the stream immediately
                httpWebRequest.AllowReadStreamBuffering = false;

                // asynchronously get a response
                httpWebRequest.BeginGetResponse( ResponseCallback, httpWebRequest );
                }
            catch ( HttpRequestException e )
                {
                Debug.WriteLine( "\nException Message :{0} ", e.Message );
                }
            }

        private void ResponseCallback( IAsyncResult asyncResult )
            {
            char[ ] Buffer = new char[ 1024 ];

            // get the response
            HttpWebRequest httpWebRequest = (HttpWebRequest)asyncResult.AsyncState;
            HttpWebResponse httpWebResponse = null;
            try
                {
                httpWebResponse = (HttpWebResponse)httpWebRequest.EndGetResponse( asyncResult );

                Stream responseStream = httpWebResponse.GetResponseStream();
                BinaryReader binaryReader = new BinaryReader( responseStream );

                Buffer = binaryReader.ReadChars( Buffer.Length );

                httpWebResponse.Close();
                }
            catch ( Exception ex )
                {
                if ( Error != null )
                    _context.Post( delegate { Error( this, new ErrorEventArgs() { Message = ex.Message } ); }, null );

                return;
                }
            }

Seems to work more reliably like this.

EitanB

Answer 5

You should use nuget and get the microsoft httpclient as eitanb states in a post rather than his accepted answer.
Your http client code would work direct out of the box.

The search name is "Microsoft Http Client Libraries", it will also install the BCL libraries.