Quels namespace pour IServerContractCallback et ServerContractClient?

Version imprimable

18/06/2013, 14h44
Masmeta

Quels namespace pour IServerContractCallback et ServerContractClient?
Bonjour à tous ,

J'étudie l'article "Développer une visionneuse d'images avec WPF et WCF" sur Tech Head Brother, posté par Thomas Lebrun.
J'essaye de comprendre ce code cependant je bloque sur les déclarations du client et surtout sur :
1. public class WCFClient : IServerContractCallback quelque est le namespace de IServerContractCallback ?
2. private ServerContractClient sc = null; : Quel est le namespace de ServerContractClient?
J'ai cherché sur la MSDN en framework 4, cependant je n'ai rien trouvé.

Pouvez vous m'éclairez sur ses deux points?
Je vous remercie,
20/06/2013, 09h58
Invité

L'auteur du tutoriel ne définie pas de Namespace pour les classes spécifiées. Il n'a mis que les définitions des classes que tu as citées. Tu copies ces classes dans ton projet avec le namespace que tu veux et tu utilises celui-ci tout au long du tuto.
20/06/2013, 18h15
Masmeta

Citation:

Envoyé par h2s84

L'auteur du tutoriel ne définie pas de Namespace pour les classes spécifiées. Il n'a mis que les définitions des classes que tu as citées. Tu copies ces classes dans ton projet avec le namespace que tu veux et tu utilises celui-ci tout au long du tuto.

C'est ce que j'ai fait mais j'ai cette erreur que je ne comprend pas
20/06/2013, 19h53
Invité

Citation:

Envoyé par Masmeta

C'est ce que j'ai fait mais j'ai cette erreur que je ne comprend pas

Sauf que nous tu nous as toujours pas fourni l'erreur dont tu parles :aie:
20/06/2013, 20h15
infosam76

h2s84 :-)

Ca fait 10 minutes que je relis la discussion en me disant que je suis aveugle

Excusez moi, je me suis mal exprimé. Les erreurs que me fournissent VS2010 sont les suivantes :

Citation:

The type or namespace name 'ServerContractClient' could not be found (are you missing a using directive or an assembly reference?)

The type or namespace name 'IServerContractCallback' could not be found (are you missing a using directive or an assembly reference?)

C'est pour cela que je me demandais quels sont les namespaces de ses classes.

Je joins mon code, ca peut aider aussi :oops:. J'ai uniquement fais du copier-coller du site avec des rajouts namespaces de Runtime .

Code:

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using System.Text;
using System.IO;
using System.ServiceModel;
using System.Runtime;
using System.Runtime.Serialization;
using System.Runtime.Remoting;
namespace test_1
{
  [ServiceContract]
    public interface IClientContract
    {
        [OperationContract(IsOneWay = true)]
        void GetImagesFromServer(List<CustomImage> img);
 
        [OperationContract(IsOneWay = true)]
        void GetUpdateFromFileShare(CustomImage img);
    }
 
 
    [ServiceContract(CallbackContract = typeof(IClientContract))]
    public interface IServerContract
    {
        [OperationContract(IsOneWay = false)]
        void StartWatcher(string path);
 
        [OperationContract(IsOneWay = false)]
        void GetImagesFromPathAtFirstLoad(string path);
    }
 
    [DataContract]
    public class CustomImage
    {
        public enum ChangeType
        {
            Add,
            Delete
        }
 
        [DataMember]
        public string Name { get; set; }
 
        [DataMember]
        public string FullPath { get; set; }
 
        [DataMember]
        public Byte[] Img { get; set; }
 
        [DataMember]
        public ChangeType Modification { get; set; }
    }
 
 
    [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, InstanceContextMode = InstanceContextMode.Single)]
    public class ServiceImplementation : IServerContract
    {
 
 
     #region Member Fields
 
        private System.IO.FileSystemWatcher fsw = null;
        private OperationContext context = null;
        private IClientContract client = null;
 
        #endregion
 
        #region IServerContract Members
 
        /// <summary>
        /// Start the FileSystemWatcher on the server.
        /// </summary>
        /// <param name="path">The path to the directory to watch.</param>
        public void StartWatcher(string path)
        {
            try
            {
                context = OperationContext.Current;
                client = context.GetCallbackChannel<IClientContract>();
 
                fsw = new System.IO.FileSystemWatcher();
                fsw.Path = path;
                fsw.IncludeSubdirectories = true;
                fsw.Filter = "*.*";
                fsw.Created += new System.IO.FileSystemEventHandler(GetUpdateFileFromFSW);
                fsw.Deleted += new System.IO.FileSystemEventHandler(GetUpdateFileFromFSW);
 
                fsw.EnableRaisingEvents = true;
            }
            catch (Exception ex)
            {
                throw new FaultException<ServerException>(new ServerException(
                    string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
            }
        }
 
        /// <summary>
        /// Retrieve the images which are in the specified folder during the startup.
        /// </summary>
        /// <param name="path">The folder to get the images.</param>
        public void GetImagesFromPathAtFirstLoad(string path)
        {
            var imgList = new List<CustomImage>();
            CustomImage image = null;
 
            foreach (var file in Directory.GetFiles(path))
            {
                try
                {
                    if (Path.GetExtension(file).ToLower() == ".png" || Path.GetExtension(file).ToLower() == ".jpg" ||
                        Path.GetExtension(file).ToLower() == ".jpeg" || Path.GetExtension(file).ToLower() == ".bmp" ||
                        Path.GetExtension(file).ToLower() == ".gif")
                    {
                        using (var stream = File.OpenRead(file))
                        {
                            if (stream.Length > 0)
                            {
                                image = new CustomImage();
 
                                image.Name = Path.GetFileName(file);
                                image.FullPath = Path.GetFullPath(file);
                                image.Modification = CustomImage.ChangeType.Add;
                            }
                        }
 
                        byte[] array = GetByteFromImage(file);
                        image.Img = array;
 
                        imgList.Add(image);
                    }
                }
                catch (Exception ex)
                {
                    throw new FaultException<ServerException>(new ServerException(
                        string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
                }
            }
 
            if (client != null)
            {
                client.GetImagesFromServer(imgList);
            }
        }
 
        #endregion
 
        /// <summary>
        /// Convert a file on a byte array.
        /// </summary>
        /// <param name="file">The file to convert.</param>
        /// <returns>An array of byte corresponding to the file.</returns>
        private static byte[] GetByteFromImage(string file)
        {
            byte[] array;
 
            try
            {
                using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read))
                {
                    BinaryReader reader = new BinaryReader(fs);
 
                    array = reader.ReadBytes((int)fs.Length);
 
                    reader.Close();
                }
            }
            catch (Exception ex)
            {
                throw new FaultException<ServerException>(new ServerException(
                    string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
            }
 
            return array;
        }
 
        /// <summary>
        /// Method called when the FileSystemWatcher detects that a file has been added/deleted.
        /// </summary>
        private void GetUpdateFileFromFSW(object sender, System.IO.FileSystemEventArgs e)
        {
            CustomImage image = null;
 
            if (e.ChangeType == System.IO.WatcherChangeTypes.Created)
            {
                if (File.Exists(e.FullPath) && (Path.GetExtension(e.FullPath).ToLower() == ".png" ||
                    Path.GetExtension(e.FullPath).ToLower() == ".jpg"
                    || Path.GetExtension(e.FullPath).ToLower() == ".jpeg" 
                    || Path.GetExtension(e.FullPath).ToLower() == ".bmp" 
                    || Path.GetExtension(e.FullPath).ToLower() == ".gif"))
                {
                    try
                    {
                        using (var stream = File.OpenRead(e.FullPath))
                        {
                            if (stream.Length > 0)
                            {
                                image = new CustomImage();
 
                                image.Name = e.Name;
                                image.FullPath = e.FullPath;
                                image.Modification = CustomImage.ChangeType.Add;
                            }
                        }
 
                        byte[] array = GetByteFromImage(e.FullPath);
                        image.Img = array;
                    }
                    catch (Exception ex)
                    {
                        throw new FaultException<ServerException>(new ServerException(
                            string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
                    }
                }
            }
            else if (e.ChangeType == System.IO.WatcherChangeTypes.Deleted)
            {
                image = new CustomImage();
 
                image.Name = e.Name;
                image.FullPath = e.FullPath;
                image.Modification = CustomImage.ChangeType.Delete;
            }
 
            if (image != null)
            {
                SendUpdateToClient(image);
            }
        }
 
        /// <summary>
        /// Inforl the client that an update is available.
        /// </summary>
        /// <param name="image">The image that have been added/deleted.</param>
        private void SendUpdateToClient(CustomImage image)
        {
            if (client != null)
            {
                client.GetUpdateFromFileShare(image);
            }
        }
 
 
    }
 
    [CallbackBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, UseSynchronizationContext = false)]
    public class WCFClient : IServerContractCallback 
    {
        #region Member Fields
 
        private ServerContractClient sc = null;
 
        public delegate void GetImagesFromServerHandler(CustomImage[] imgList);
        public event GetImagesFromServerHandler GetImagesFromServerEvent;
 
        public delegate void GetUpdateFromFileShareHandler(CustomImage img);
        public event GetUpdateFromFileShareHandler GetUpdateFromFileShareEvent;
 
        #endregion
 
        /// <summary>
        /// Public constructor.
        /// </summary>
        public WCFClient()
        {
            sc = new ServerContractClient(new System.ServiceModel.InstanceContext(this));
 
            sc.Open();
        }
 
        /// <summary>
        /// Ask the service to launch the FileSystemWatcher on the server.
        /// </summary>
        /// <param name="path">The folder to watch on the server.</param>
        public void StartWatcher(string path)
        {
            sc.StartWatcher(path);
        }
 
        /// <summary>
        /// Ask the service to get the images which are in the dedicated folder.
        /// </summary>
        /// <param name="path">The folder that you want the images.</param>
        public void GetImagesFromPathAtFirstLoad(string path)
        {
            try
            {
                sc.GetImagesFromPathAtFirstLoad(path);
            }
            catch (ServerException ex)
            {
                throw new FaultException<ServerException>(new ServerException(
                    string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
            }
        }
 
        /// <summary>
        /// Disconnect the client from the service.
        /// </summary>
        public void Disconnect()
        {
            sc.Close();
        }
 
        #region IServerContractCallback Members
 
        /// <summary>
        /// Method called when the service pushed the images to the client.
        /// </summary>
        /// <param name="imgList">The list of images to load/get from the server.</param>
        public void GetImagesFromServer(CustomImage[] imgList)
        {
            if (GetImagesFromServerEvent != null)
            {
                GetImagesFromServerEvent(imgList);
            }
        }
 
        /// <summary>
        /// Method called when the service detext an update in the folder where the image are stored.
        /// </summary>
        /// <param name="img">The image that has been added/removed from the folder</param>
        public void GetUpdateFromFileShare(CustomImage img)
        {
            if (GetUpdateFromFileShareEvent != null)
            {
                GetUpdateFromFileShareEvent(img);
            }
        }
 
        #endregion
    }
}

24/06/2013, 09h28
Invité

Les classes IServerContractCallback et ServerContractClient ne sont pas tombées du ciel comme ça. Tu les utilises dans ton code sans pour autant mettre dans ton code les définitions de ces dites classes. Ces classes comme dit plus haut sont à la page 2 du tutoriel. Ces deux classes ne sont pas de .Net mais créées par le développeur. Suis de A à Z le tutoriel en respectant les noms des classes fournies et normalement tu n'auras pas ce problème. Ensuite tu pourras renommer ces classes à ta sauce. :ccool:
24/06/2013, 10h34
Masmeta

Bonjour,

Citation:

Envoyé par h2s84

Suis de A à Z le tutoriel en respectant les noms des classes fournies et normalement tu n'auras pas ce problème. Ensuite tu pourras renommer ces classes à ta sauce. :ccool:

Je l'ai refais plusieurs fois soit dans ma solution ( un projet WCF Service et un projet WPF), ou dans une nouvelle solution. J'ai toujours le même soucis.

La classe IServerContractCallback n'est pas IServerContract, et malgré mes différentes relectures, je ne l'a trouve pas dans le tuto, idem pour la classe ServerContractClient .

C'est le même code que le tuto et peux-tu me dire ce qui ne marche pas ?

Code:

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[ServiceContract(CallbackContract = typeof(IClientContract))]
    public interface IServerContract
    {
        [OperationContract(IsOneWay = false)]
        void StartWatcher(string path);
 
        [OperationContract(IsOneWay = false)]
        void GetImagesFromPathAtFirstLoad(string path);
    }
 
    [ServiceContract]
    public interface IClientContract
    {
        [OperationContract(IsOneWay = true)]
        void GetImagesFromServer(List<CustomImage> img);
 
        [OperationContract(IsOneWay = true)]
        void GetUpdateFromFileShare(CustomImage img);
    }
 
    [DataContract]
    public class CustomImage
    {
        public enum ChangeType
        {
            Add,
            Delete
        }
 
        [DataMember]
        public string Name { get; set; }
 
        [DataMember]
        public string FullPath { get; set; }
 
        [DataMember]
        public Byte[] Img { get; set; }
 
        [DataMember]
        public ChangeType Modification { get; set; }
    }
 
    [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, InstanceContextMode = InstanceContextMode.Single)]
    public class ServiceImplementation : IServerContract
    {
        #region Member Fields
 
        private System.IO.FileSystemWatcher fsw = null;
        private OperationContext context = null;
        private IClientContract client = null;
 
        #endregion
 
        #region IServerContract Members
 
        /// <summary>
        /// Start the FileSystemWatcher on the server.
        /// </summary>
        /// <param name="path">The path to the directory to watch.</param>
        public void StartWatcher(string path)
        {
            try
            {
                context = OperationContext.Current;
                client = context.GetCallbackChannel<IClientContract>();
 
                fsw = new System.IO.FileSystemWatcher();
                fsw.Path = path;
                fsw.IncludeSubdirectories = true;
                fsw.Filter = "*.*";
                fsw.Created += new System.IO.FileSystemEventHandler(GetUpdateFileFromFSW);
                fsw.Deleted += new System.IO.FileSystemEventHandler(GetUpdateFileFromFSW);
 
                fsw.EnableRaisingEvents = true;
            }
            catch (Exception ex)
            {
                throw new FaultException<ServerException>(new ServerException(
                    string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
            }
        }
 
        /// <summary>
        /// Retrieve the images which are in the specified folder during the startup.
        /// </summary>
        /// <param name="path">The folder to get the images.</param>
        public void GetImagesFromPathAtFirstLoad(string path)
        {
            var imgList = new List<CustomImage>();
            CustomImage image = null;
 
            foreach (var file in Directory.GetFiles(path))
            {
                try
                {
                    if (Path.GetExtension(file).ToLower() == ".png" || Path.GetExtension(file).ToLower() == ".jpg" ||
                        Path.GetExtension(file).ToLower() == ".jpeg" || Path.GetExtension(file).ToLower() == ".bmp" ||
                        Path.GetExtension(file).ToLower() == ".gif")
                    {
                        using (var stream = File.OpenRead(file))
                        {
                            if (stream.Length > 0)
                            {
                                image = new CustomImage();
 
                                image.Name = Path.GetFileName(file);
                                image.FullPath = Path.GetFullPath(file);
                                image.Modification = CustomImage.ChangeType.Add;
                            }
                        }
 
                        byte[] array = GetByteFromImage(file);
                        image.Img = array;
 
                        imgList.Add(image);
                    }
                }
                catch (Exception ex)
                {
                    throw new FaultException<ServerException>(new ServerException(
                        string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
                }
            }
 
            if (client != null)
            {
                client.GetImagesFromServer(imgList);
            }
        }
 
        #endregion
 
        /// <summary>
        /// Convert a file on a byte array.
        /// </summary>
        /// <param name="file">The file to convert.</param>
        /// <returns>An array of byte corresponding to the file.</returns>
        private static byte[] GetByteFromImage(string file)
        {
            byte[] array;
 
            try
            {
                using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read))
                {
                    BinaryReader reader = new BinaryReader(fs);
 
                    array = reader.ReadBytes((int)fs.Length);
 
                    reader.Close();
                }
            }
            catch (Exception ex)
            {
                throw new FaultException<ServerException>(new ServerException(
                    string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
            }
 
            return array;
        }
 
        /// <summary>
        /// Method called when the FileSystemWatcher detects that a file has been added/deleted.
        /// </summary>
        private void GetUpdateFileFromFSW(object sender, System.IO.FileSystemEventArgs e)
        {
            CustomImage image = null;
 
            if (e.ChangeType == System.IO.WatcherChangeTypes.Created)
            {
                if (File.Exists(e.FullPath) && (Path.GetExtension(e.FullPath).ToLower() == ".png" ||
                    Path.GetExtension(e.FullPath).ToLower() == ".jpg"
                    || Path.GetExtension(e.FullPath).ToLower() == ".jpeg"
                    || Path.GetExtension(e.FullPath).ToLower() == ".bmp"
                    || Path.GetExtension(e.FullPath).ToLower() == ".gif"))
                {
                    try
                    {
                        using (var stream = File.OpenRead(e.FullPath))
                        {
                            if (stream.Length > 0)
                            {
                                image = new CustomImage();
 
                                image.Name = e.Name;
                                image.FullPath = e.FullPath;
                                image.Modification = CustomImage.ChangeType.Add;
                            }
                        }
 
                        byte[] array = GetByteFromImage(e.FullPath);
                        image.Img = array;
                    }
                    catch (Exception ex)
                    {
                        throw new FaultException<ServerException>(new ServerException(
                            string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
                    }
                }
            }
            else if (e.ChangeType == System.IO.WatcherChangeTypes.Deleted)
            {
                image = new CustomImage();
 
                image.Name = e.Name;
                image.FullPath = e.FullPath;
                image.Modification = CustomImage.ChangeType.Delete;
            }
 
            if (image != null)
            {
                SendUpdateToClient(image);
            }
        }
 
        /// <summary>
        /// Inforl the client that an update is available.
        /// </summary>
        /// <param name="image">The image that have been added/deleted.</param>
        private void SendUpdateToClient(CustomImage image)
        {
            if (client != null)
            {
                client.GetUpdateFromFileShare(image);
            }
        }

Citation:

Envoyé par h2s84

C'est le même code que le tuto et peux-tu me dire ce qui ne marche pas ?

Ce code marche très bien. Je parle du code sur le client du service WCF

Code:

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 [CallbackBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, UseSynchronizationContext = false)]
    public class WCFClient : IServerContractCallback
    {
        #region Member Fields
 
        private ServerContractClient sc = null;
 
        public delegate void GetImagesFromServerHandler(CustomImage[] imgList);
        public event GetImagesFromServerHandler GetImagesFromServerEvent;
 
        public delegate void GetUpdateFromFileShareHandler(CustomImage img);
        public event GetUpdateFromFileShareHandler GetUpdateFromFileShareEvent;
 
        #endregion
 
        /// <summary>
        /// Public constructor.
        /// </summary>
        public WCFClient()
        {
            sc = new ServerContractClient(new System.ServiceModel.InstanceContext(this));
 
            sc.Open();
        }
 
        /// <summary>
        /// Ask the service to launch the FileSystemWatcher on the server.
        /// </summary>
        /// <param name="path">The folder to watch on the server.</param>
        public void StartWatcher(string path)
        {
            sc.StartWatcher(path);
        }
 
        /// <summary>
        /// Ask the service to get the images which are in the dedicated folder.
        /// </summary>
        /// <param name="path">The folder that you want the images.</param>
        public void GetImagesFromPathAtFirstLoad(string path)
        {
            try
            {
                sc.GetImagesFromPathAtFirstLoad(path);
            }
            catch (ServerException ex)
            {
                throw new FaultException<ServerException>(new ServerException(
                    string.Format("An error occured !{0}{1}", Environment.NewLine, ex.Message)));
            }
        }
 
        /// <summary>
        /// Disconnect the client from the service.
        /// </summary>
        public void Disconnect()
        {
            sc.Close();
        }
 
        #region IServerContractCallback Members
 
        /// <summary>
        /// Method called when the service pushed the images to the client.
        /// </summary>
        /// <param name="imgList">The list of images to load/get from the server.</param>
        public void GetImagesFromServer(CustomImage[] imgList)
        {
            if (GetImagesFromServerEvent != null)
            {
                GetImagesFromServerEvent(imgList);
            }
        }
 
        /// <summary>
        /// Method called when the service detext an update in the folder where the image are stored.
        /// </summary>
        /// <param name="img">The image that has been added/removed from the folder</param>
        public void GetUpdateFromFileShare(CustomImage img)
        {
            if (GetUpdateFromFileShareEvent != null)
            {
                GetUpdateFromFileShareEvent(img);
            }
        }
 
        #endregion
    }