Επεξεργασία

Κοινή χρήση μέσω


XmlAttributeOverrides.Add Method

Definition

Adds an XmlAttributes object to the collection of XmlAttributes objects.

Overloads

Add(Type, XmlAttributes)

Adds an XmlAttributes object to the collection of XmlAttributes objects. The type parameter specifies an object to be overridden by the XmlAttributes object.

Add(Type, String, XmlAttributes)

Adds an XmlAttributes object to the collection of XmlAttributes objects. The type parameter specifies an object to be overridden. The member parameter specifies the name of a member that is overridden.

Add(Type, XmlAttributes)

Source:
XmlAttributeOverrides.cs
Source:
XmlAttributeOverrides.cs
Source:
XmlAttributeOverrides.cs

Adds an XmlAttributes object to the collection of XmlAttributes objects. The type parameter specifies an object to be overridden by the XmlAttributes object.

public:
 void Add(Type ^ type, System::Xml::Serialization::XmlAttributes ^ attributes);
public void Add (Type type, System.Xml.Serialization.XmlAttributes attributes);
member this.Add : Type * System.Xml.Serialization.XmlAttributes -> unit
Public Sub Add (type As Type, attributes As XmlAttributes)

Parameters

type
Type

The Type of the object that is overridden.

attributes
XmlAttributes

An XmlAttributes object that represents the overriding attributes.

Examples

The following example serializes a class named Band which is derived from a class named Orchestra. The example creates an XmlRootAttribute object, and assigns it to the XmlRoot property of an XmlAttributes object. The example then calls the Add method to add the XmlAttributes object to the XmlAttributeOverrides object.

#using <System.Xml.dll>
#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml::Serialization;

ref class Band;
ref class Instrument;

/* This is the class that will be overridden. The XmlIncludeAttribute 
tells the XmlSerializer that the overriding type exists. */

[XmlInclude(Band::typeid)]
public ref class Orchestra
{
public:
   array<Instrument^>^Instruments;
};

// This is the overriding class.
public ref class Band: public Orchestra
{
public:
   String^ BandName;
};

public ref class Instrument
{
public:
   String^ Name;
};

void SerializeObject( String^ filename )
{
   /* Each object that is being overridden requires 
      an XmlAttributes object. */
   XmlAttributes^ attrs = gcnew XmlAttributes;

   // An XmlRootAttribute allows overriding the Orchestra class.
   XmlRootAttribute^ xmlRoot = gcnew XmlRootAttribute;

   // Set the object to the XmlAttribute.XmlRoot property.
   attrs->XmlRoot = xmlRoot;

   // Create an XmlAttributeOverrides object.
   XmlAttributeOverrides^ attrOverrides = gcnew XmlAttributeOverrides;

   // Add the XmlAttributes to the XmlAttributeOverrrides.
   attrOverrides->Add( Orchestra::typeid, attrs );

   // Create the XmlSerializer using the XmlAttributeOverrides.
   XmlSerializer^ s = gcnew XmlSerializer( Orchestra::typeid,attrOverrides );

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

   // Create the object using the derived class.
   Band^ band = gcnew Band;
   band->BandName = "NewBand";

   // Create an Instrument.
   Instrument^ i = gcnew Instrument;
   i->Name = "Trumpet";
   array<Instrument^>^myInstruments = {i};
   band->Instruments = myInstruments;

   // Serialize the object.
   s->Serialize( writer, band );
   writer->Close();
}

void DeserializeObject( String^ filename )
{
   XmlAttributes^ attrs = gcnew XmlAttributes;
   XmlRootAttribute^ attr = gcnew XmlRootAttribute;
   attrs->XmlRoot = attr;
   XmlAttributeOverrides^ attrOverrides = gcnew XmlAttributeOverrides;
   attrOverrides->Add( Orchestra::typeid, "Instruments", attrs );
   XmlSerializer^ s = gcnew XmlSerializer( Orchestra::typeid,attrOverrides );
   FileStream^ fs = gcnew FileStream( filename,FileMode::Open );

   // Deserialize the Band object.
   Band^ band = dynamic_cast<Band^>(s->Deserialize( fs ));
   Console::WriteLine( "Brass:" );
   System::Collections::IEnumerator^ myEnum = band->Instruments->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Instrument^ i = safe_cast<Instrument^>(myEnum->Current);
      Console::WriteLine( i->Name );
   }
}

int main()
{
   SerializeObject( "Override.xml" );
   DeserializeObject( "Override.xml" );
}
using System;
using System.IO;
using System.Xml.Serialization;

/* This is the class that will be overridden. The XmlIncludeAttribute
tells the XmlSerializer that the overriding type exists. */

[XmlInclude(typeof(Band))]
public class Orchestra
{
   public Instrument[] Instruments;
}

// This is the overriding class.
public class Band:Orchestra
{
   public string BandName;
}

public class Instrument
{
   public string Name;
}

public class Run
{
    public static void Main()
    {
       Run test = new Run();
       test.SerializeObject("Override.xml");
       test.DeserializeObject("Override.xml");
    }

    public void SerializeObject(string filename)
    {
      /* Each object that is being overridden requires
      an XmlAttributes object. */
      XmlAttributes attrs = new XmlAttributes();

      // An XmlRootAttribute allows overriding the Orchestra class.
      XmlRootAttribute xmlRoot = new XmlRootAttribute();

      // Set the object to the XmlAttribute.XmlRoot property.
      attrs.XmlRoot = xmlRoot;

      // Create an XmlAttributeOverrides object.
      XmlAttributeOverrides attrOverrides =
      new XmlAttributeOverrides();

      // Add the XmlAttributes to the XmlAttributeOverrrides.
      attrOverrides.Add(typeof(Orchestra), attrs);

      // Create the XmlSerializer using the XmlAttributeOverrides.
      XmlSerializer s =
      new XmlSerializer(typeof(Orchestra), attrOverrides);

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

      // Create the object using the derived class.
      Band band = new Band();
      band.BandName = "NewBand";

      // Create an Instrument.
      Instrument i = new Instrument();
      i.Name = "Trumpet";
      Instrument[] myInstruments = {i};
      band.Instruments = myInstruments;

      // Serialize the object.
      s.Serialize(writer,band);
      writer.Close();
   }

   public void DeserializeObject(string filename)
   {
      XmlAttributes attrs = new XmlAttributes();
      XmlRootAttribute attr = new XmlRootAttribute();
      attrs.XmlRoot = attr;
      XmlAttributeOverrides attrOverrides =
         new XmlAttributeOverrides();

      attrOverrides.Add(typeof(Orchestra), "Instruments", attrs);

      XmlSerializer s =
      new XmlSerializer(typeof(Orchestra), attrOverrides);

      FileStream fs = new FileStream(filename, FileMode.Open);

      // Deserialize the Band object.
      Band band = (Band) s.Deserialize(fs);
      Console.WriteLine("Brass:");

      foreach(Instrument i in band.Instruments)
      {
         Console.WriteLine(i.Name);
      }
   }
}
Option Explicit
Option Strict

Imports System.IO
Imports System.Xml.Serialization


' This is the class that will be overridden. The XmlIncludeAttribute
' tells the XmlSerializer that the overriding type exists. 
<XmlInclude(GetType(Band))> _
Public Class Orchestra
    Public Instruments() As Instrument
End Class

' This is the overriding class.
Public Class Band
    Inherits Orchestra
    Public BandName As String
End Class

Public Class Instrument
    Public Name As String
End Class

Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("Override.xml")
        test.DeserializeObject("Override.xml")
    End Sub    
    
    Public Sub SerializeObject(ByVal filename As String)
        ' Each object that is being overridden requires
        ' an XmlAttributes object. 
        Dim attrs As New XmlAttributes()
        
        ' An XmlRootAttribute allows overriding the Orchestra class.
        Dim xmlRoot As New XmlRootAttribute()
        
        ' Set the object to the XmlAttribute.XmlRoot property.
        attrs.XmlRoot = xmlRoot
        
        ' Create an XmlAttributeOverrides object.
        Dim attrOverrides As New XmlAttributeOverrides()
        
        ' Add the XmlAttributes to the XmlAttributeOverrrides.
        attrOverrides.Add(GetType(Orchestra), attrs)
        
        ' Create the XmlSerializer using the XmlAttributeOverrides.
        Dim s As New XmlSerializer(GetType(Orchestra), attrOverrides)
        
        ' Writing the file requires a TextWriter.
        Dim writer As New StreamWriter(filename)
        
        ' Create the object using the derived class.
        Dim band As New Band()
        band.BandName = "NewBand"
        
        ' Create an Instrument.
        Dim i As New Instrument()
        i.Name = "Trumpet"
        Dim myInstruments() As Instrument = {i}
        band.Instruments = myInstruments
        
        ' Serialize the object.
        s.Serialize(writer, band)
        writer.Close()
    End Sub    
    
    Public Sub DeserializeObject(ByVal filename As String)
        Dim attrs As New XmlAttributes()
        Dim attr As New XmlRootAttribute()
        attrs.XmlRoot = attr
        Dim attrOverrides As New XmlAttributeOverrides()
        
        attrOverrides.Add(GetType(Orchestra), "Instruments", attrs)
        
        Dim s As New XmlSerializer(GetType(Orchestra), attrOverrides)
        
        Dim fs As New FileStream(filename, FileMode.Open)
        
        ' Deserialize the Band object.
        Dim band As Band = CType(s.Deserialize(fs), Band)
        Console.WriteLine("Brass:")
        
        Dim i As Instrument
        For Each i In  band.Instruments
            Console.WriteLine(i.Name)
        Next i
    End Sub
End Class

Remarks

The XmlAttributes object contains a union of attribute objects that cause the XmlSerializer to override its default serialization behavior for a set of objects. You choose the attribute objects to place in the XmlAttributes object, depending on the particular behaviors you want to override. For example, the XmlSerializer serializes a class member as an XML element by default. If you want the member to be serialized as an XM attribute instead, you would create an XmlAttributeAttribute, assign it to the XmlAttribute property of an XmlAttributes, and add the XmlAttributes object to the XmlAttributeOverrides object.

Use this overload to override an XmlRootAttribute or XmlTypeAttribute.

See also

Applies to

Add(Type, String, XmlAttributes)

Source:
XmlAttributeOverrides.cs
Source:
XmlAttributeOverrides.cs
Source:
XmlAttributeOverrides.cs

Adds an XmlAttributes object to the collection of XmlAttributes objects. The type parameter specifies an object to be overridden. The member parameter specifies the name of a member that is overridden.

public:
 void Add(Type ^ type, System::String ^ member, System::Xml::Serialization::XmlAttributes ^ attributes);
public void Add (Type type, string member, System.Xml.Serialization.XmlAttributes attributes);
public void Add (Type type, string member, System.Xml.Serialization.XmlAttributes? attributes);
member this.Add : Type * string * System.Xml.Serialization.XmlAttributes -> unit
Public Sub Add (type As Type, member As String, attributes As XmlAttributes)

Parameters

type
Type

The Type of the object to override.

member
String

The name of the member to override.

attributes
XmlAttributes

An XmlAttributes object that represents the overriding attributes.

Examples

The following example creates an XmlAttributeAttribute object, and assigns it to the XmlAttribute property of an XmlAttributes object. The example then adds the XmlAttributes object to an XmlAttributeOverrides object, before creating an XmlSerializer.

// This is the class that will be serialized.
public ref class Group
{
public:
   String^ GroupName;

   [XmlAttributeAttribute]
   int GroupCode;
};

public ref class Sample
{
public:
   XmlSerializer^ CreateOverrider()
   {
      // Create an XmlAttributeOverrides object. 
      XmlAttributeOverrides^ xOver = gcnew XmlAttributeOverrides;

      /* Create an XmlAttributeAttribute to override the base class
            object's XmlAttributeAttribute object. Give the overriding object
            a new attribute name ("Code"). */
      XmlAttributeAttribute^ xAtt = gcnew XmlAttributeAttribute;
      xAtt->AttributeName = "Code";

      /* Create an instance of the XmlAttributes class and set the 
            XmlAttribute property to the XmlAttributeAttribute object. */
      XmlAttributes^ attrs = gcnew XmlAttributes;
      attrs->XmlAttribute = xAtt;

      /* Add the XmlAttributes object to the XmlAttributeOverrides
            and specify the type and member name to override. */
      xOver->Add( Group::typeid, "GroupCode", attrs );
      XmlSerializer^ xSer = gcnew XmlSerializer( Group::typeid,xOver );
      return xSer;
   }
};
// This is the class that will be serialized.
public class Group
{
   public string GroupName;
   [XmlAttribute]
   public int GroupCode;
}

public class Sample
{
public XmlSerializer CreateOverrider()
{
   // Create an XmlAttributeOverrides object.
   XmlAttributeOverrides xOver = new XmlAttributeOverrides();

   /* Create an XmlAttributeAttribute to override the base class
   object's XmlAttributeAttribute object. Give the overriding object
   a new attribute name ("Code"). */
   XmlAttributeAttribute xAtt = new XmlAttributeAttribute();
   xAtt.AttributeName = "Code";

   /* Create an instance of the XmlAttributes class and set the
   XmlAttribute property to the XmlAttributeAttribute object. */
   XmlAttributes attrs = new XmlAttributes();
   attrs.XmlAttribute = xAtt;

   /* Add the XmlAttributes object to the XmlAttributeOverrides
      and specify the type and member name to override. */
   xOver.Add(typeof(Group), "GroupCode", attrs);

   XmlSerializer xSer = new XmlSerializer(typeof(Group), xOver);
   return xSer;
}
}
' This is the class that will be serialized.
Public Class Group
    Public GroupName As String
    <XmlAttribute()> Public GroupCode As Integer
End Class

Public Class Sample
    
    Public Function CreateOverrider() As XmlSerializer
        ' Create an XmlAttributeOverrides object. 
        Dim xOver As New XmlAttributeOverrides()
        
        ' Create an XmlAttributeAttribute to override the base class
        ' object's XmlAttributeAttribute object. Give the overriding object
        ' a new attribute name ("Code").
        Dim xAtt As New XmlAttributeAttribute()
        xAtt.AttributeName = "Code"
        
        ' Create an instance of the XmlAttributes class and set the
        ' XmlAttribute property to the XmlAttributeAttribute object. 
        Dim attrs As New XmlAttributes()
        attrs.XmlAttribute = xAtt
        
        ' Add the XmlAttributes object to the XmlAttributeOverrides
        ' and specify the type and member name to override. 
        xOver.Add(GetType(Group), "GroupCode", attrs)
        
        Dim xSer As New XmlSerializer(GetType(Group), xOver)
        Return xSer
    End Function
End Class

Remarks

The XmlAttributes object contains a union of attribute objects that cause the XmlSerializer to override its default serialization behavior for a set of objects. You choose the attribute objects to place in the XmlAttributes object, depending on the particular behaviors you want to override. For example, the XmlSerializer serializes a class member as an XML element by default. If you want the member to be serialized as an XML attribute instead, you would create an XmlAttributeAttribute, assign it to the XmlAttribute property of an XmlAttributes, and add the XmlAttributes object to the XmlAttributeOverrides object.

Use this method when attempting to override an XmlElementAttribute, XmlAttributeAttribute, XmlArrayAttribute, XmlArrayItemAttribute, or XmlIgnoreAttribute.

See also

Applies to