SoapAttributes.SoapDefaultValue Eigenschap

public:
 property System::Object ^ SoapDefaultValue { System::Object ^ get(); void set(System::Object ^ value); };

public object? SoapDefaultValue { get; set; }

public object SoapDefaultValue { get; set; }

member this.SoapDefaultValue : obj with get, set

Public Property SoapDefaultValue As Object

Waarde van eigenschap

Een object dat de standaardwaarde van een XML-element of kenmerk vertegenwoordigt.

Voorbeelden

In het volgende voorbeeld wordt een klasse geserialiseerd Group die een veld met de naam GroupNamebevat. De standaardwaarde wordt ingesteld met de DefaultValueAttribute op '.NET'. Door het veld niet in te stellen of door het in te stellen op '.NET', wordt de waarde niet geserialiseerd (omdat de standaardwaarde al bekend is). Het voorbeeld overschrijft ook de standaardwaarde in de CreateOverrideSerializer methode, die door de SerializeOverride methode wordt aangeroepen. In het voorbeeld worden beide methoden aangeroepen, SerializeOriginal en SerializeOverride, en wordt dezelfde waarde ('.NET') ingesteld voor het veld GroupName. Vanwege de onderdrukking wordt de waarde alleen geserialiseerd wanneer de SerializeOverride methode wordt aangeroepen.

using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using System.Xml.Schema;
using System.ComponentModel;

public class Group
{
   // The default is set to .NET.
   [DefaultValue(".NET")]
   public string GroupName;
}

public class Run
{
   public static void Main()
   {
      Run test = new Run();
      test.SerializeOriginal("SoapOriginal.xml");
      test.SerializeOverride("mySoapAttributeOverridesideAttributes.xml");
      test.DeserializeOriginal("SoapOriginal.xml");
      test.DeserializeOverride("mySoapAttributeOverridesideAttributes.xml");
   }
   public void SerializeOriginal(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlSerializer mySerializer =
      new XmlSerializer(typeof(Group));

      // Writing the file requires a TextWriter.
      TextWriter writer = new StreamWriter(filename);

      // Create an instance of the class that will be serialized.
      Group myGroup = new Group();

      // Setting the GroupName to '.NET' is like not setting it at all
      // because it is the default value. So no value will be
      // serialized, and on deserialization it will appear as a blank.
      myGroup.GroupName = ".NET";

      // Serialize the class, and close the TextWriter.
      mySerializer.Serialize(writer, myGroup);
      writer.Close();
   }

   public void SerializeOverride(string filename)
   {
      // Create an instance of the XmlSerializer class
      // that overrides the serialization.
      XmlSerializer overRideSerializer = CreateOverrideSerializer();

      // Writing the file requires a TextWriter.
      TextWriter writer = new StreamWriter(filename);

      // Create an instance of the class that will be serialized.
      Group myGroup = new Group();

      // The override specifies that the default value is now
      // 'Team1'. So setting the GroupName to '.NET' means
      // the value will be serialized.
      myGroup.GroupName = ".NET";
      // Serialize the class, and close the TextWriter.
      overRideSerializer.Serialize(writer, myGroup);
       writer.Close();
   }

   public void DeserializeOriginal(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlSerializer mySerializer= new XmlSerializer(typeof(Group));
      // Reading the file requires a TextReader.
      TextReader reader = new StreamReader(filename);

      // Deserialize and cast the object.
      Group myGroup;
      myGroup = (Group) mySerializer.Deserialize(reader);

      Console.WriteLine(myGroup.GroupName);
      Console.WriteLine();
   }

   public void DeserializeOverride(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlSerializer overRideSerializer = CreateOverrideSerializer();
      // Reading the file requires a TextReader.
      TextReader reader = new StreamReader(filename);

      // Deserialize and cast the object.
      Group myGroup;
      myGroup = (Group) overRideSerializer.Deserialize(reader);

      Console.WriteLine(myGroup.GroupName);
   }

   private XmlSerializer CreateOverrideSerializer()
   {
      SoapAttributeOverrides mySoapAttributeOverrides =
      new SoapAttributeOverrides();
      SoapAttributes soapAtts = new SoapAttributes();
      // Create a new DefaultValueAttribute object for the GroupName
      // property.
      DefaultValueAttribute newDefault =
      new DefaultValueAttribute("Team1");
      soapAtts.SoapDefaultValue = newDefault;

      mySoapAttributeOverrides.Add(typeof(Group), "GroupName",
      soapAtts);

      // Create an XmlTypeMapping that is used to create an instance
      // of the XmlSerializer. Then return the XmlSerializer object.
      XmlTypeMapping myMapping = (new SoapReflectionImporter(
      mySoapAttributeOverrides)).ImportTypeMapping(typeof(Group));
    
      XmlSerializer ser = new XmlSerializer(myMapping);
      return ser;
   }
}

Imports System.IO
Imports System.Xml
Imports System.Xml.Serialization
Imports System.Xml.Schema
Imports System.ComponentModel

Public Class Group
   ' The default is set to .NET.
   <DefaultValue(".NET")> _
   Public GroupName As String
End Class
 
Public Class Run

   Public Shared Sub Main()
   
      Dim test As Run = new Run()
      test.SerializeOriginal("SoapOriginal.xml")
      test.SerializeOverride _
      ("mySoapAttributeOverridesideAttributes.xml")
      test.DeserializeOriginal("SoapOriginal.xml")
      test.DeserializeOverride _
      ("mySoapAttributeOverridesideAttributes.xml")
   End Sub
   
   public Sub SerializeOriginal(filename As String)
       ' Create an instance of the XmlSerializer class.
      Dim mySerializer As XmlSerializer =  _
      new XmlSerializer(GetType(Group))

      ' Writing the file requires a TextWriter.
      Dim writer As TextWriter = new StreamWriter(filename)

      ' Create an instance of the class that will be serialized.
      Dim myGroup As Group = new Group()

      ' Setting the GroupName to '.NET' is like not setting it at all
      ' because it is the default value. So no value will be 
      ' serialized, and on deserialization it will appear as a blank.
      myGroup.GroupName = ".NET"

      ' Serialize the class, and close the TextWriter.
      mySerializer.Serialize(writer, myGroup)
      writer.Close()
   End Sub

   Public Sub SerializeOverride(filename As String)
   
      ' Create an instance of the XmlSerializer class
      ' that overrides the serialization.
      Dim overRideSerializer As XmlSerializer = CreateOverrideSerializer()

      ' Writing the file requires a TextWriter.
      Dim writer As TextWriter = new StreamWriter(filename)

      ' Create an instance of the class that will be serialized.
      Dim myGroup As Group = new Group()

      ' The override specifies that the default value is now 
      ' 'Team1'. So setting the GroupName to '.NET' means
      ' the value will be serialized.
      myGroup.GroupName = ".NET"
      ' Serialize the class, and close the TextWriter.
      overRideSerializer.Serialize(writer, myGroup)
       writer.Close()

   End Sub


   Public Sub DeserializeOriginal(filename As String)
   
      ' Create an instance of the XmlSerializer class.
      Dim mySerializer As XmlSerializer = new XmlSerializer(GetType(Group))
      ' Reading the file requires a TextReader.
      Dim reader As TextReader = new StreamReader(filename)

      ' Deserialize and cast the object.
      Dim myGroup As Group = CType(mySerializer.Deserialize(reader), Group)

      Console.WriteLine(myGroup.GroupName)
      Console.WriteLine()
   End Sub

   Public Sub DeserializeOverride(filename As String)
   
      ' Create an instance of the XmlSerializer class.
      Dim overRideSerializer As XmlSerializer = CreateOverrideSerializer()
      ' Reading the file requires a TextReader.
      Dim reader As TextReader = new StreamReader(filename)

      ' Deserialize and cast the object.
      Dim myGroup As Group = CType(overRideSerializer.Deserialize(reader), Group)

      Console.WriteLine(myGroup.GroupName)

   End Sub

   Private Function CreateOverrideSerializer() As XmlSerializer 
   
      Dim mySoapAttributeOverrides As SoapAttributeOverrides  = _
      New SoapAttributeOverrides()
      Dim soapAtts As SoapAttributes = New SoapAttributes()
      ' Create a new DefaultValueAttribute object for the GroupName
      ' property.
      Dim newDefault As DefaultValueAttribute = _
      new DefaultValueAttribute("Team1")
      soapAtts.SoapDefaultValue = newDefault

     mySoapAttributeOverrides.Add(GetType(Group), "GroupName", _
     soapAtts)
      
      ' Create an XmlTypeMapping that is used to create an instance 
      ' of the XmlSerializer. Then return the XmlSerializer object.
      Dim myMapping As XmlTypeMapping = _
      (New SoapReflectionImporter( _
      mySoapAttributeOverrides)).ImportTypeMapping(GetType(Group))
    
      Dim ser As XmlSerializer = new XmlSerializer(myMapping)
      return ser
   End Function
End Class

Opmerkingen

De standaardwaarde van een lid kan worden ingesteld door een DefaultValueAttribute kenmerk toe te passen op het lid. Als het lid wordt geserialiseerd als een gecodeerd SOAP-bericht, kunt u de standaardwaarde wijzigen door een nieuwe DefaultValueAttributeValue eigenschap te maken en de SoapDefaultValue eigenschap in te stellen op het object. Voeg het SoapAttributes toe aan een SoapAttributeOverrides. Zie het SoapAttributeOverrides klasoverzicht voor meer informatie.

Zie ook

• XmlAttributes
• Kenmerken waarmee gecodeerde SOAP-serialisatie wordt beheerd
• Procedure: Een object serialiseren als een SOAP-Encoded XML-stroom