BodyWriter Classe

Definição

public ref class BodyWriter abstract

public abstract class BodyWriter

type BodyWriter = class

Public MustInherit Class BodyWriter

Herança

Object

BodyWriter

Derivado

System.ServiceModel.Channels.StreamBodyWriter

System.ServiceModel.Security.WSTrustRequestBodyWriter

System.ServiceModel.Security.WSTrustResponseBodyWriter

Exemplos

O exemplo seguinte mostra como derivar uma classe a partir de BodyWriter. Este override recebe um array de strings e escreve-as num 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

Observações

Uma mensagem consiste em cabeçalhos e um corpo. Os cabeçalhos são armazenados em buffer e o corpo é transmitido em streaming. Como o corpo é transmitido em streaming, o utilizador não pode passar o conteúdo real do corpo para uma mensagem. Em vez disso, o utilizador deve passar numa classe que sabe escrever o corpo quando solicitado. Isto faz-se passando uma classe derivada de BodyWriter para o Message. Uma mensagem chama a classe derivada de BodyWriter sempre que exige que o corpo seja escrito usando um XmlWriter.