Vorgehensweise: Erstellen eines grundlegenden Atom-FeedsHow to: Create a Basic Atom Feed

Windows Communication Foundation (WCF)Windows Communication Foundation (WCF) ermöglicht Ihnen die Erstellung eines Diensts, der einen Syndication-Feed verfügbar macht. allows you to create a service that exposes a syndication feed. In diesem Thema wird erläutert, wie ein Syndication-Dienst erstellt wird, der einen Atom-Syndication-Feed verfügbar macht.This topic discusses how to create a syndication service that exposes an Atom syndication feed.

So erstellen Sie einen grundlegenden Syndication-DienstTo create a basic syndication service

  1. Definieren Sie einen Dienstvertrag mit einer Schnittstelle, die mit dem WebGetAttribute-Attribut gekennzeichnet ist.Define a service contract using an interface marked with the WebGetAttribute attribute. Jeder Vorgang, der als Syndication-Feed verfügbar gemacht wird, sollte ein Atom10FeedFormatter-Objekt zurückgeben.Each operation that is exposed as a syndication feed should return a Atom10FeedFormatter object.

    [ServiceContract]
    public interface IBlog
    {
        [OperationContract]
        [WebGet]
        Atom10FeedFormatter GetBlog();
    }
    
    <ServiceContract()> _
    Public Interface IBlog
        <OperationContract()> _
        <WebGet> _
        Function GetBlog() As Atom10FeedFormatter
    End Interface
    

    Hinweis

    Alle Dienstvorgänge, auf die das WebGetAttribute-Attribut angewendet wird, werden HTTP GET-Anforderungen zugeordnet.All service operations that apply the WebGetAttribute are mapped to HTTP GET requests. Wenn Sie den Vorgang einer anderen HTTP-Methode zuordnen möchten, verwenden Sie stattdessen WebInvokeAttribute.To map your operation to a different HTTP method, use the WebInvokeAttribute instead. Weitere Informationen finden Sie unterFor more information, seeVorgehensweise: Erstellen eines grundlegenden WCF-Web-HTTP-Diensts. How to: Create a Basic WCF Web HTTP Service.

  2. Implementieren Sie den Dienstvertrag.Implement the service contract.

    public class BlogService : IBlog
    {
        public Atom10FeedFormatter GetBlog()
        {
            SyndicationFeed feed = new SyndicationFeed("My Blog Feed", "This is a test feed", new Uri("http://SomeURI"), "FeedOneID", new DateTimeOffset(DateTime.Now));
            feed.Authors.Add(new SyndicationPerson("someone@microsoft.com"));
            feed.Categories.Add(new SyndicationCategory("How To Sample Code"));
            feed.Description = new TextSyndicationContent("This is a sample that illistrates how to expose a feed using ATOM with WCF");
    
            SyndicationItem item1 = new SyndicationItem(
                "Item One",
                "This is the content for item one",
                new Uri("http://localhost/Content/One"),
                "ItemOneID",
                DateTime.Now);
    
            SyndicationItem item2 = new SyndicationItem(
                "Item Two",
                "This is the content for item two",
                new Uri("http://localhost/Content/Two"),
                "ItemTwoID",
                DateTime.Now);
    
            SyndicationItem item3 = new SyndicationItem(
                "Item Three",
                "This is the content for item three",
                new Uri("http://localhost/Content/three"),
                "ItemThreeID",
                DateTime.Now);
            List<SyndicationItem> items = new List<SyndicationItem>();
    
            items.Add(item1);
            items.Add(item2);
            items.Add(item3);
    
            feed.Items = items;
            return new Atom10FeedFormatter(feed);
        }
    }
    
    Public Class BlogService
        Implements IBlog
        Public Function GetBlog() As Atom10FeedFormatter Implements IBlog.GetBlog
            Dim feed As New SyndicationFeed("My Blog Feed", "This is a test feed", New Uri("http://SomeURI"), "FeedOneID", new DateTimeOffset(DateTime.Now))
            feed.Authors.Add(New SyndicationPerson("someone@microsoft.com"))
            feed.Categories.Add(New SyndicationCategory("How To Sample Code"))
            feed.Description = New TextSyndicationContent("This is a sample that illistrates how to expose a feed imports ATOM with WCF")
    
            Dim item1 As New SyndicationItem( _
                "Item One", _
                "This is the content for item one", _
                New Uri("http://localhost/Content/One"), _
                "ItemOneID", _
                DateTime.Now)
    
            Dim item2 As New SyndicationItem( _
                "Item Two", _
                "This is the content for item two", _
                New Uri("http://localhost/Content/Two"), _
                "ItemTwoID", _
                DateTime.Now)
    
            Dim item3 As New SyndicationItem( _
                "Item Three", _
                "This is the content for item three", _
                New Uri("http://localhost/Content/three"), _
                "ItemThreeID", _
                DateTime.Now)
            Dim items As New List(Of SyndicationItem)()
    
            items.Add(item1)
            items.Add(item2)
            items.Add(item3)
    
            feed.Items = items
            Return New Atom10FeedFormatter(feed)
        End Function
    End Class
    
  3. Erstellen Sie ein SyndicationFeed-Objekt, und fügen Sie einen Autor, eine Kategorie und eine Beschreibung hinzu.Create a SyndicationFeed object and add an author, category, and description.

    SyndicationFeed feed = new SyndicationFeed("My Blog Feed", "This is a test feed", new Uri("http://SomeURI"), "FeedOneID", new DateTimeOffset(DateTime.Now));
    feed.Authors.Add(new SyndicationPerson("someone@microsoft.com"));
    feed.Categories.Add(new SyndicationCategory("How To Sample Code"));
    feed.Description = new TextSyndicationContent("This is a sample that illistrates how to expose a feed using ATOM with WCF");
    
    Dim feed As New SyndicationFeed("My Blog Feed", "This is a test feed", New Uri("http://SomeURI"), "FeedOneID", new DateTimeOffset(DateTime.Now))
    feed.Authors.Add(New SyndicationPerson("someone@microsoft.com"))
    feed.Categories.Add(New SyndicationCategory("How To Sample Code"))
    feed.Description = New TextSyndicationContent("This is a sample that illistrates how to expose a feed imports ATOM with WCF")
    
  4. Erstellen Sie mehrere SyndicationItem-Objekte.Create several SyndicationItem objects.

    SyndicationItem item1 = new SyndicationItem(
        "Item One",
        "This is the content for item one",
        new Uri("http://localhost/Content/One"),
        "ItemOneID",
        DateTime.Now);
    
    SyndicationItem item2 = new SyndicationItem(
        "Item Two",
        "This is the content for item two",
        new Uri("http://localhost/Content/Two"),
        "ItemTwoID",
        DateTime.Now);
    
    SyndicationItem item3 = new SyndicationItem(
        "Item Three",
        "This is the content for item three",
        new Uri("http://localhost/Content/three"),
        "ItemThreeID",
        DateTime.Now);
    
    Dim item1 As New SyndicationItem( _
        "Item One", _
        "This is the content for item one", _
        New Uri("http://localhost/Content/One"), _
        "ItemOneID", _
        DateTime.Now)
    
    Dim item2 As New SyndicationItem( _
        "Item Two", _
        "This is the content for item two", _
        New Uri("http://localhost/Content/Two"), _
        "ItemTwoID", _
        DateTime.Now)
    
    Dim item3 As New SyndicationItem( _
        "Item Three", _
        "This is the content for item three", _
        New Uri("http://localhost/Content/three"), _
        "ItemThreeID", _
        DateTime.Now)
    
  5. Fügen Sie die SyndicationItem-Objekte dem Feed hinzu.Add the SyndicationItem objects to the feed.

    List<SyndicationItem> items = new List<SyndicationItem>();
    
    items.Add(item1);
    items.Add(item2);
    items.Add(item3);
    
    feed.Items = items;
    
    Dim items As New List(Of SyndicationItem)()
    
    items.Add(item1)
    items.Add(item2)
    items.Add(item3)
    
    feed.Items = items
    
  6. Geben Sie den Feed zurück.Return the feed.

    return new Atom10FeedFormatter(feed);
    
    Return New Atom10FeedFormatter(feed)
    

So hosten Sie den DienstTo host the service

  1. Erstellen eines WebServiceHost-ObjektsCreate a WebServiceHost object.

    Uri baseAddress = new Uri("http://localhost:8000/BlogService/");
    WebServiceHost svcHost = new WebServiceHost(typeof(BlogService), baseAddress);
    
    Dim baseAddress As New Uri("http://localhost:8000/BlogService/")
    Dim svcHost As New WebServiceHost(GetType(BlogService), baseAddress)
    
  2. Öffnen Sie den Diensthost, laden Sie den Feed vom Dienst, zeigen Sie den Feed an, und warten Sie darauf, dass der Benutzer die Eingabetaste drückt.Open the service host, load the feed from the service, display the feed, and wait for the user to press ENTER.

    svcHost.Open();
    Console.WriteLine("Service is running");
    
    XmlReader reader = XmlReader.Create("http://localhost:8000/BlogService/GetBlog");
    SyndicationFeed feed = SyndicationFeed.Load(reader);
    Console.WriteLine(feed.Title.Text);
    Console.WriteLine("Items:");
    foreach (SyndicationItem item in feed.Items)
    {
        Console.WriteLine("Title: {0}", item.Title.Text);
        Console.WriteLine("Content: {0}", ((TextSyndicationContent)item.Content).Text);
    }
    Console.WriteLine("Press <ENTER> to quit...");
    Console.ReadLine();
    svcHost.Close();
    
    svcHost.Open()
    Console.WriteLine("Service is running")
    
    Dim reader As XmlReader = XmlReader.Create("http://localhost:8000/BlogService/GetBlog")
    Dim feed As SyndicationFeed = SyndicationFeed.Load(reader)
    Console.WriteLine(feed.Title.Text)
    Console.WriteLine("Items:")
    
    For Each item As SyndicationItem In feed.Items
        Console.WriteLine("Title: {0}", item.Title.Text)
        Console.WriteLine("Content: {0}", item.Title.Text)
    Next
    
    Console.WriteLine("Press <ENTER> to quit...")
    Console.ReadLine()
    svcHost.Close()
    

So rufen Sie GetBlog() mit HTTP GET aufTo call GetBlog() with an HTTP GET

  1. Öffnen Sie den Internet Explorer, geben Sie die folgende URL ein, und drücken Sie die EINGABETASTE: http://localhost:8000/BlogService/GetBlog.Open Internet Explorer, type the following URL, and press ENTER: http://localhost:8000/BlogService/GetBlog

    Die URL enthält die Basisadresse des Diensts (http://localhost:8000/BlogService), die relative Adresse des Endpunkts und den aufzurufenden Dienstvorgang.The URL contains the base address of the service (http://localhost:8000/BlogService), the relative address of the endpoint, and the service operation to call.

So rufen Sie GetBlog() aus dem Code aufTo call GetBlog() from code

  1. Erstellen Sie einen XmlReader mit der Basisadresse und der Methode, die Sie aufrufen.Create a XmlReader with the base address and the method you are calling.

    XmlReader reader = XmlReader.Create("http://localhost:8000/BlogService/GetBlog");
    
    Dim serviceAddress As New Uri("http://localhost:8000/BlogService/GetBlog")
    
  2. Rufen Sie die statische Load(XmlReader)-Methode auf, und übergeben Sie dabei den gerade erstellten XmlReader.Call the static Load(XmlReader) method, passing in the XmlReader you just created.

    SyndicationFeed feed = SyndicationFeed.Load(reader);
    
    Dim feed As SyndicationFeed = SyndicationFeed.Load(serviceAddress)
    

    Dies ruft einen Dienstvorgang auf und füllt einen neuen SyndicationFeed mit dem vom Dienstvorgang zurückgegebenen Formatierungsprogramm auf.This invokes the service operation and populates a new SyndicationFeed with the formatter returned from the service operation.

  3. Greifen Sie auf das Feedobjekt zu.Access the feed object.

    Console.WriteLine(feed.Title.Text);
    Console.WriteLine("Items:");
    foreach (SyndicationItem item in feed.Items)
    {
        Console.WriteLine("Title: {0}", item.Title.Text);
        Console.WriteLine("Summary: {0}", ((TextSyndicationContent)item.Summary).Text);
    }
    
    Console.WriteLine(feed.Title.Text)
    Console.WriteLine("Items:")
    For Each item As SyndicationItem In feed.Items
        Console.WriteLine("Title: {0}", item.Title.Text)
        Console.WriteLine("Summary: {0}", item.Summary.Text)
    Next
    

BeispielExample

Unten ist die vollständige Codeauflistung für dieses Beispiel angegeben.The following is the full code listing for this example.

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ServiceModel;
using System.Xml;
using System.ServiceModel.Description;
using System.ServiceModel.Syndication;
using System.ServiceModel.Channels;
using System.ServiceModel.Web;

namespace Service
{
    [ServiceContract]
    public interface IBlog
    {
        [OperationContract]
        [WebGet]
        Atom10FeedFormatter GetBlog();
    }

    public class BlogService : IBlog
    {
        public Atom10FeedFormatter GetBlog()
        {
            SyndicationFeed feed = new SyndicationFeed("My Blog Feed", "This is a test feed", new Uri("http://SomeURI"), "FeedOneID", new DateTimeOffset(DateTime.Now));
            feed.Authors.Add(new SyndicationPerson("someone@microsoft.com"));
            feed.Categories.Add(new SyndicationCategory("How To Sample Code"));
            feed.Description = new TextSyndicationContent("This is a sample that illistrates how to expose a feed using ATOM with WCF");

            SyndicationItem item1 = new SyndicationItem(
                "Item One",
                "This is the content for item one",
                new Uri("http://localhost/Content/One"),
                "ItemOneID",
                DateTime.Now);

            SyndicationItem item2 = new SyndicationItem(
                "Item Two",
                "This is the content for item two",
                new Uri("http://localhost/Content/Two"),
                "ItemTwoID",
                DateTime.Now);

            SyndicationItem item3 = new SyndicationItem(
                "Item Three",
                "This is the content for item three",
                new Uri("http://localhost/Content/three"),
                "ItemThreeID",
                DateTime.Now);
            List<SyndicationItem> items = new List<SyndicationItem>();

            items.Add(item1);
            items.Add(item2);
            items.Add(item3);

            feed.Items = items;
            return new Atom10FeedFormatter(feed);
        }
    }

    public class Host
    {
        static void Main(string[] args)
        {
            Uri baseAddress = new Uri("http://localhost:8000/BlogService/");
            WebServiceHost svcHost = new WebServiceHost(typeof(BlogService), baseAddress);
            try
            {
                svcHost.Open();
                Console.WriteLine("Service is running");

                XmlReader reader = XmlReader.Create("http://localhost:8000/BlogService/GetBlog");
                SyndicationFeed feed = SyndicationFeed.Load(reader);
                Console.WriteLine(feed.Title.Text);
                Console.WriteLine("Items:");
                foreach (SyndicationItem item in feed.Items)
                {
                    Console.WriteLine("Title: {0}", item.Title.Text);
                    Console.WriteLine("Content: {0}", ((TextSyndicationContent)item.Content).Text);
                }
                Console.WriteLine("Press <ENTER> to quit...");
                Console.ReadLine();
                svcHost.Close();
            }
            catch (CommunicationException ce)
            {
                Console.WriteLine("An exception occurred: {0}", ce.Message);
                svcHost.Abort();
            }
        }
    }
}
Imports System
Imports System.Xml
Imports System.Collections.Generic
Imports System.Collections.ObjectModel
Imports System.ServiceModel
Imports System.ServiceModel.Description
Imports System.ServiceModel.Syndication
Imports System.ServiceModel.Channels
Imports System.ServiceModel.Web

<ServiceContract()> _
Public Interface IBlog
    <OperationContract()> _
    <WebGet> _
    Function GetBlog() As Atom10FeedFormatter
End Interface

Public Class BlogService
    Implements IBlog
    Public Function GetBlog() As Atom10FeedFormatter Implements IBlog.GetBlog
        Dim feed As New SyndicationFeed("My Blog Feed", "This is a test feed", New Uri("http://SomeURI"), "FeedOneID", new DateTimeOffset(DateTime.Now))
        feed.Authors.Add(New SyndicationPerson("someone@microsoft.com"))
        feed.Categories.Add(New SyndicationCategory("How To Sample Code"))
        feed.Description = New TextSyndicationContent("This is a sample that illistrates how to expose a feed imports ATOM with WCF")

        Dim item1 As New SyndicationItem( _
            "Item One", _
            "This is the content for item one", _
            New Uri("http://localhost/Content/One"), _
            "ItemOneID", _
            DateTime.Now)

        Dim item2 As New SyndicationItem( _
            "Item Two", _
            "This is the content for item two", _
            New Uri("http://localhost/Content/Two"), _
            "ItemTwoID", _
            DateTime.Now)

        Dim item3 As New SyndicationItem( _
            "Item Three", _
            "This is the content for item three", _
            New Uri("http://localhost/Content/three"), _
            "ItemThreeID", _
            DateTime.Now)
        Dim items As New List(Of SyndicationItem)()

        items.Add(item1)
        items.Add(item2)
        items.Add(item3)

        feed.Items = items
        Return New Atom10FeedFormatter(feed)
    End Function
End Class

Module Program

    Sub Main()
        Dim baseAddress As New Uri("http://localhost:8000/BlogService/")
        Dim svcHost As New WebServiceHost(GetType(BlogService), baseAddress)
        Try
            svcHost.AddServiceEndpoint(GetType(IBlog), New WebHttpBinding(), "")
            svcHost.Open()
            Console.WriteLine("Service is running")

            Dim reader As XmlReader = XmlReader.Create("http://localhost:8000/BlogService/GetBlog")
            Dim feed As SyndicationFeed = SyndicationFeed.Load(reader)
            Console.WriteLine(feed.Title.Text)
            Console.WriteLine("Items:")

            For Each item As SyndicationItem In feed.Items
                Console.WriteLine("Title: {0}", item.Title.Text)
                Console.WriteLine("Content: {0}", item.Title.Text)
            Next

            Console.WriteLine("Press <ENTER> to quit...")
            Console.ReadLine()
            svcHost.Close()

        Catch ce As CommunicationException
            Console.WriteLine("An exception occured: {0}", ce.Message)
            svcHost.Abort()
        End Try
    End Sub

End Module

Kompilieren des CodesCompiling the Code

Verweisen Sie beim Kompilieren des obigen Codes auf System.ServiceModel.dll und System.ServiceModel.Web.dll.When compiling the preceding code, reference System.ServiceModel.dll and System.ServiceModel.Web.dll.

Siehe auchSee Also

WebHttpBinding
WebGetAttribute