.NET Framework Class Library
XmlAttributeAttribute Class

Specifies that the XmlSerializer must serialize the class member as an XML attribute.

Inheritance Hierarchy
SystemObject
   SystemAttribute
    System.Xml.SerializationXmlAttributeAttribute

Namespace:   System.Xml.Serialization
Assemblies:   System.Xml.XmlSerializer (in System.Xml.XmlSerializer.dll)
  System.Xml (in System.Xml.dll)
Syntax
<[%$TOPIC/d8db82dk_en-us_VS_110_3_0_0_0_0%]([%$TOPIC/d8db82dk_en-us_VS_110_3_0_0_0_1%].Property Or [%$TOPIC/d8db82dk_en-us_VS_110_3_0_0_0_2%].Field Or [%$TOPIC/d8db82dk_en-us_VS_110_3_0_0_0_3%].Parameter Or [%$TOPIC/d8db82dk_en-us_VS_110_3_0_0_0_4%].ReturnValue)> _
Public Class XmlAttributeAttribute _
	Inherits [%$TOPIC/d8db82dk_en-us_VS_110_3_0_0_0_5%]
[[%$TOPIC/d8db82dk_en-us_VS_110_3_0_1_0_0%]([%$TOPIC/d8db82dk_en-us_VS_110_3_0_1_0_1%].Property|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_1_0_2%].Field|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_1_0_3%].Parameter|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_1_0_4%].ReturnValue)]
public class XmlAttributeAttribute : [%$TOPIC/d8db82dk_en-us_VS_110_3_0_1_0_5%]
[[%$TOPIC/d8db82dk_en-us_VS_110_3_0_2_0_0%]([%$TOPIC/d8db82dk_en-us_VS_110_3_0_2_0_1%]::Property|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_2_0_2%]::Field|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_2_0_3%]::Parameter|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_2_0_4%]::ReturnValue)]
public ref class XmlAttributeAttribute : public [%$TOPIC/d8db82dk_en-us_VS_110_3_0_2_0_5%]
[<[%$TOPIC/d8db82dk_en-us_VS_110_3_0_3_0_0%]([%$TOPIC/d8db82dk_en-us_VS_110_3_0_3_0_1%].Property|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_3_0_2%].Field|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_3_0_3%].Parameter|[%$TOPIC/d8db82dk_en-us_VS_110_3_0_3_0_4%].ReturnValue)>]
type XmlAttributeAttribute =  
    class 
        inherit [%$TOPIC/d8db82dk_en-us_VS_110_3_0_3_0_5%] 
    end
public class XmlAttributeAttribute extends [%$TOPIC/d8db82dk_en-us_VS_110_3_0_4_0_0%]

The XmlAttributeAttribute type exposes the following members.

Constructors
  NameDescription
Public method Supported by the XNA Framework Supported by Portable Class Library XmlAttributeAttributeInitializes a new instance of the XmlAttributeAttribute class.
Public method Supported by the XNA Framework Supported by Portable Class Library XmlAttributeAttribute(String)Initializes a new instance of the XmlAttributeAttribute class and specifies the name of the generated XML attribute.
Public method Supported by the XNA Framework Supported by Portable Class Library XmlAttributeAttribute(Type)Initializes a new instance of the XmlAttributeAttribute class.
Public method Supported by the XNA Framework Supported by Portable Class Library XmlAttributeAttribute(String, Type)Initializes a new instance of the XmlAttributeAttribute class.
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Properties
  NameDescription
Public property Supported by the XNA Framework Supported by Portable Class Library AttributeNameGets or sets the name of the XML attribute.
Public property Supported by the XNA Framework Supported by Portable Class Library DataTypeGets or sets the XSD data type of the XML attribute generated by the XmlSerializer.
Public property Supported by the XNA Framework Supported by Portable Class Library FormGets or sets a value that indicates whether the XML attribute name generated by the XmlSerializer is qualified.
Public property Supported by the XNA Framework Supported by Portable Class Library NamespaceGets or sets the XML namespace of the XML attribute.
Public property Supported by the XNA Framework Supported by Portable Class Library TypeGets or sets the complex type of the XML attribute.
Public property TypeIdWhen implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)
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Methods
  NameDescription
Public method Supported by the XNA Framework Supported by Portable Class Library EqualsInfrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)
Protected method Supported by the XNA Framework Supported by Portable Class Library FinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method Supported by the XNA Framework Supported by Portable Class Library GetHashCodeReturns the hash code for this instance. (Inherited from Attribute.)
Public method Supported by the XNA Framework Supported by Portable Class Library GetTypeGets the Type of the current instance. (Inherited from Object.)
Public method IsDefaultAttributeWhen overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.)
Public method Supported by the XNA Framework MatchWhen overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Protected method Supported by the XNA Framework Supported by Portable Class Library MemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public method Supported by the XNA Framework Supported by Portable Class Library ToStringReturns a string that represents the current object. (Inherited from Object.)
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Explicit Interface Implementations
  NameDescription
Explicit interface implemetation Private method _AttributeGetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetation Private method _AttributeGetTypeInfoRetrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetation Private method _AttributeGetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetation Private method _AttributeInvokeProvides access to properties and methods exposed by an object. (Inherited from Attribute.)
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Remarks

The XmlAttributeAttribute belongs to a family of attributes that controls how the XmlSerializer serializes, or deserializes, an object. For a complete list of similar attributes, see Attributes That Control XML Serialization.

When applied to a public field or property, the XmlAttributeAttribute informs the XmlSerializer to serialize the member as an XML attribute. By default, the XmlSerializer serializes public fields and properties as XML elements.

You can assign the XmlAttributeAttribute only to public fields or public properties that return a value (or array of values) that can be mapped to one of the XML Schema definition language (XSD) simple types (including all built-in datatypes derived from the XSD anySimpleType type). The possible types include any that can be mapped to the XSD simple types, including Guid, Char, and enumerations. See the DataType property for a list of XSD types and how they are mapped to.NET data types.

There are two special attributes that can be set with the XmlAttributeAttribute : the xml:lang (specifies language) and xml:space (specifies how to handle white space) attributes. These attributes are intended to convey information that is relevant only to an application processing the XML. Examples of setting these are shown in the following code.

[XmlAttribute("xml:lang")]
 public string Lang;
 // Set this to 'default' or 'preserve'.
 [XmlAttribute("space", 
 Namespace = "http://www.w3.org/XML/1998/namespace")]
 public string Space 
 [Visual Basic]
 <XmlAttribute("xml:lang")> _
 Public Lang As String 
 ' Set this to 'default' or 'preserve'.
 <XmlAttribute("space", _
 Namespace:= "http://www.w3.org/XML/1998/namespace")> _
 Public Space As String

For more information about using attributes, see Extending Metadata Using Attributes.

NoteNote

You can use the word XmlAttribute in your code instead of the longer XmlAttributeAttribute.

Examples

The following example serializes a class that contains several fields to which the XmlAttributeAttribute is applied.

Option Explicit
Option Strict

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


Public Class Group
    <XmlAttribute(Namespace := "http://www.cpandl.com")> _
        Public GroupName As String    
    <XmlAttribute(DataType := "base64Binary")> _
        Public GroupNumber() As Byte    
    <XmlAttribute(DataType := "date", AttributeName := "CreationDate")> _
        Public Today As DateTime
End Class 

Public Class Run

    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("Attributes.xml")
    End Sub  

    Public Sub SerializeObject(ByVal filename As String)
        ' Create an instance of the XmlSerializer class. 
        Dim mySerializer As New XmlSerializer(GetType(Group))

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

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

        ' Set the object properties.
        myGroup.GroupName = ".NET" 

        Dim hexByte() As Byte = {Convert.ToByte(100), Convert.ToByte(50)}
        myGroup.GroupNumber = hexByte

        Dim myDate As New DateTime(2001, 1, 10)
        myGroup.Today = myDate

        ' Serialize the class, and close the TextWriter.
        mySerializer.Serialize(writer, myGroup)
        writer.Close()
    End Sub 
End Class
using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using System.Xml.Schema;

public class Group
{
   [XmlAttribute (Namespace = "http://www.cpandl.com")]
   public string GroupName;

   [XmlAttribute(DataType = "base64Binary")]
   public Byte [] GroupNumber;

   [XmlAttribute(DataType = "date", AttributeName = "CreationDate")]
   public DateTime Today;
}



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


   public void SerializeObject(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();

      // Set the object properties.
      myGroup.GroupName = ".NET";

      Byte [] hexByte = new Byte[2]{Convert.ToByte(100),
      Convert.ToByte(50)};
      myGroup.GroupNumber = hexByte;

      DateTime myDate = new DateTime(2001,1,10);
      myGroup.Today = myDate;

      // Serialize the class, and close the TextWriter.
      mySerializer.Serialize(writer, myGroup);
       writer.Close();
   }
}
   
#using <System.Xml.dll>
#using <System.dll>

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

public ref class Group
{
public:

   [XmlAttributeAttribute(Namespace="http://www.cpandl.com")]
   String^ GroupName;

   [XmlAttributeAttribute(DataType="base64Binary")]
   array<Byte>^GroupNumber;

   [XmlAttributeAttribute(DataType="date",AttributeName="CreationDate")]
   DateTime Today;
};

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

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

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

   // Set the object properties.
   myGroup->GroupName = ".NET";
   array<Byte>^hexByte = {Convert::ToByte( 100 ),Convert::ToByte( 50 )};
   myGroup->GroupNumber = hexByte;
   DateTime myDate = DateTime(2001,1,10);
   myGroup->Today = myDate;

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

int main()
{
   SerializeObject( "Attributes.xml" );
}
Version Information

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.