BodyWriter Classe

Definizione

public ref class BodyWriter abstract

public abstract class BodyWriter

type BodyWriter = class

Public MustInherit Class BodyWriter

Ereditarietà

Object

BodyWriter

Derivato

System.ServiceModel.Channels.StreamBodyWriter

System.ServiceModel.Security.WSTrustRequestBodyWriter

System.ServiceModel.Security.WSTrustResponseBodyWriter

Esempio

Nell'esempio seguente viene illustrato come derivare una classe da BodyWriter. Questa override accetta una matrice di stringhe e le scrive in un oggetto XmlDictionaryWriter.

using System;
using System.Text;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.Xml;

namespace UEBodyWriter
{
    class MyBodyWriter : BodyWriter
    {
        const string textTag = "text";
        string[] bodySegment;

        public MyBodyWriter(string[] strData) : base(true)
        {
            int length = strData.Length;

            this.bodySegment = new string[length];
            for (int i = 0; i < length; i++)
            {
                this.bodySegment[i] = strData[i];
            }
        }

        protected override void OnWriteBodyContents(XmlDictionaryWriter writer)
        {
           writer.WriteStartElement(textTag);

           foreach (string str in bodySegment)
           {
               writer.WriteString(str);
           }

            writer.WriteEndElement();
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            string[] strings = {"Hello", "world"};
            MyBodyWriter bw = new MyBodyWriter(strings);

            StringBuilder strBuilder = new StringBuilder(10);
            XmlWriter writer = XmlWriter.Create(strBuilder);
            XmlDictionaryWriter dictionaryWriter = XmlDictionaryWriter.CreateDictionaryWriter(writer);

            bw.WriteBodyContents(dictionaryWriter);
            dictionaryWriter.Flush();
        }
    }
}

Imports System.Text
Imports System.ServiceModel
Imports System.ServiceModel.Channels
Imports System.Xml

Namespace UEBodyWriter
    Friend Class MyBodyWriter
        Inherits BodyWriter
        Private Const textTag As String = "text"
        Private bodySegment() As String

        Public Sub New(ByVal strData() As String)
            MyBase.New(True)
            Dim length = strData.Length

            Me.bodySegment = New String(length - 1){}
            For i = 0 To length - 1
                Me.bodySegment(i) = strData(i)
            Next i
        End Sub

        Protected Overrides Sub OnWriteBodyContents(ByVal writer As XmlDictionaryWriter)
           writer.WriteStartElement(textTag)

            For Each str As String In bodySegment
                writer.WriteString(str)
            Next str

            writer.WriteEndElement()
        End Sub
    End Class

    Module Module1
        Sub Main(ByVal args() As String)
            Dim strings() As String = {"Hello", "world"}
            Dim bw As New MyBodyWriter(strings)

            Dim strBuilder As New StringBuilder(10)
            Dim writer = XmlWriter.Create(strBuilder)
            Dim dictionaryWriter = XmlDictionaryWriter.CreateDictionaryWriter(writer)

            bw.WriteBodyContents(dictionaryWriter)
            dictionaryWriter.Flush()
        End Sub
    End Module
End Namespace

Commenti

Un messaggio è costituito da intestazioni e un corpo. Le intestazioni vengono memorizzate nel buffer e il corpo viene trasmesso. Poiché il corpo viene trasmesso, l'utente non può passare il contenuto effettivo del corpo a un messaggio. L'utente deve invece passare una classe che sa scrivere il corpo quando viene richiesto di farlo. A tale scopo, passare una classe derivata da BodyWriter a Message. Un messaggio chiama la classe derivata da BodyWriter ogni volta che richiede che il corpo venga scritto usando un oggetto XmlWriter.