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XmlAttributes.XmlEnum Property

Definition

Gets or sets an object that specifies how the XmlSerializer serializes an enumeration member.

public:
 property System::Xml::Serialization::XmlEnumAttribute ^ XmlEnum { System::Xml::Serialization::XmlEnumAttribute ^ get(); void set(System::Xml::Serialization::XmlEnumAttribute ^ value); };
public System.Xml.Serialization.XmlEnumAttribute XmlEnum { get; set; }
public System.Xml.Serialization.XmlEnumAttribute? XmlEnum { get; set; }
member this.XmlEnum : System.Xml.Serialization.XmlEnumAttribute with get, set
Public Property XmlEnum As XmlEnumAttribute

Property Value

An XmlEnumAttribute that specifies how the XmlSerializer serializes an enumeration member.

Examples

The following example serializes two classes named Food and FoodType. The FoodType class contains two enumerations that are overridden and, for each enumeration, the example creates an XmlEnumAttribute object that it assigns to the XmlEnum property of an XmlAttributes object. The example then adds the XmlAttributes object to an XmlAttributeOverrides object, which is used to create an XmlSerializer.

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

using namespace System;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Serialization;
public enum class FoodType
{
   // Subsequent code overrides these enumerations.
   Low, High
};

// This is the class that will be serialized.
public ref class Food
{
public:
   FoodType Type;
};

// Return an XmlSerializer used for overriding. 
XmlSerializer^ CreateOverrider()
{
   // Create the XmlAttributeOverrides and XmlAttributes objects.
   XmlAttributeOverrides^ xOver = gcnew XmlAttributeOverrides;
   XmlAttributes^ xAttrs = gcnew XmlAttributes;

   // Add an XmlEnumAttribute for the FoodType.Low enumeration.
   XmlEnumAttribute^ xEnum = gcnew XmlEnumAttribute;
   xEnum->Name = "Cold";
   xAttrs->XmlEnum = xEnum;
   xOver->Add( FoodType::typeid, "Low", xAttrs );

   // Add an XmlEnumAttribute for the FoodType.High enumeration.
   xAttrs = gcnew XmlAttributes;
   xEnum = gcnew XmlEnumAttribute;
   xEnum->Name = "Hot";
   xAttrs->XmlEnum = xEnum;
   xOver->Add( FoodType::typeid, "High", xAttrs );

   // Create the XmlSerializer, and return it.
   return gcnew XmlSerializer( Food::typeid,xOver );
}

void SerializeObject( String^ filename )
{
   // Create an instance of the XmlSerializer class.
   XmlSerializer^ mySerializer = CreateOverrider();

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

   // Create an instance of the class that will be serialized.
   Food^ myFood = gcnew Food;

   // Set the object properties.
   myFood->Type = FoodType::High;

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

void DeserializeObject( String^ filename )
{
   XmlSerializer^ mySerializer = CreateOverrider();
   FileStream^ fs = gcnew FileStream( filename,FileMode::Open );
   Food^ myFood = dynamic_cast<Food^>(mySerializer->Deserialize( fs ));
   Console::WriteLine( myFood->Type );
}

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

// This is the class that will be serialized.
public class Food
{
   public FoodType Type;
}

public enum FoodType
{
   // Subsequent code overrides these enumerations.
   Low,
   High
}

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

   // Return an XmlSerializer used for overriding.
   public XmlSerializer CreateOverrider()
   {
      // Create the XmlAttributeOverrides and XmlAttributes objects.
      XmlAttributeOverrides xOver = new XmlAttributeOverrides();
      XmlAttributes xAttrs = new XmlAttributes();

      // Add an XmlEnumAttribute for the FoodType.Low enumeration.
      XmlEnumAttribute xEnum = new XmlEnumAttribute();
      xEnum.Name = "Cold";
      xAttrs.XmlEnum = xEnum;
      xOver.Add(typeof(FoodType), "Low", xAttrs);

      // Add an XmlEnumAttribute for the FoodType.High enumeration.
      xAttrs = new XmlAttributes();
      xEnum = new XmlEnumAttribute();
      xEnum.Name = "Hot";
      xAttrs.XmlEnum = xEnum;
      xOver.Add(typeof(FoodType), "High", xAttrs);

      // Create the XmlSerializer, and return it.
      return new XmlSerializer(typeof(Food), xOver);
   }

   public void SerializeObject(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlSerializer mySerializer =  CreateOverrider();
      // Writing the file requires a TextWriter.
      TextWriter writer = new StreamWriter(filename);

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

      // Set the object properties.
      myFood.Type = FoodType.High;

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

   public void DeserializeObject(string filename)
   {
      XmlSerializer mySerializer = CreateOverrider();
      FileStream fs = new FileStream(filename, FileMode.Open);
      Food myFood = (Food)
      mySerializer.Deserialize(fs);

      Console.WriteLine(myFood.Type);
   }
}
Imports System.IO
Imports System.Xml
Imports System.Xml.Serialization


' This is the class that will be serialized.
Public Class Food
    Public Type As FoodType
End Class

Public Enum FoodType
    ' Subsequent code overrides these enumerations.
    Low
    High
End Enum


Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("OverrideEnum.xml")
        test.DeserializeObject("OverrideEnum.xml")
    End Sub
    
    
    ' Return an XmlSerializer used for overriding. 
    Public Function CreateOverrider() As XmlSerializer
        ' Create the XmlAttributeOverrides and XmlAttributes objects.
        Dim xOver As New XmlAttributeOverrides()
        Dim xAttrs As New XmlAttributes()
        
        ' Add an XmlEnumAttribute for the FoodType.Low enumeration.
        Dim xEnum As New XmlEnumAttribute()
        xEnum.Name = "Cold"
        xAttrs.XmlEnum = xEnum
        xOver.Add(GetType(FoodType), "Low", xAttrs)
        
        ' Add an XmlEnumAttribute for the FoodType.High enumeration.
        xAttrs = New XmlAttributes()
        xEnum = New XmlEnumAttribute()
        xEnum.Name = "Hot"
        xAttrs.XmlEnum = xEnum
        xOver.Add(GetType(FoodType), "High", xAttrs)
        
        ' Create the XmlSerializer, and return it.
        Return New XmlSerializer(GetType(Food), xOver)
    End Function
    
        
    Public Sub SerializeObject(ByVal filename As String)
        ' Create an instance of the XmlSerializer class.
        Dim mySerializer As XmlSerializer = CreateOverrider()
        ' Writing the file requires a TextWriter.
        Dim writer As New StreamWriter(filename)
        
        ' Create an instance of the class that will be serialized.
        Dim myFood As New Food()
        
        ' Set the object properties.
        myFood.Type = FoodType.High
        
        ' Serialize the class, and close the TextWriter.
        mySerializer.Serialize(writer, myFood)
        writer.Close()
    End Sub
    
    
    Public Sub DeserializeObject(ByVal filename As String)
        Dim mySerializer As XmlSerializer = CreateOverrider()
        Dim fs As New FileStream(filename, FileMode.Open)
        Dim myFood As Food = CType(mySerializer.Deserialize(fs), Food)
        
        Console.WriteLine(myFood.Type)
    End Sub
End Class

Remarks

For each identifier you want to override, you must create an XmlAttributes object, and set the XmlEnum property to an XmlEnumAttribute that overrides the identifier. Add the XmlAttributes object to the XmlAttributeOverrides object and specify both the Type of the class that contains the enumeration, and the overridden member name.

Applies to