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XmlRootAttribute Class

Definition

Controls XML serialization of the attribute target as an XML root element.

public ref class XmlRootAttribute : Attribute
[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Enum | System.AttributeTargets.Interface | System.AttributeTargets.ReturnValue | System.AttributeTargets.Struct)]
public class XmlRootAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Enum | System.AttributeTargets.Interface | System.AttributeTargets.ReturnValue | System.AttributeTargets.Struct)>]
type XmlRootAttribute = class
    inherit Attribute
Public Class XmlRootAttribute
Inherits Attribute
Inheritance
XmlRootAttribute
Attributes

Examples

The following example applies the XmlRootAttribute to a class. The attribute specifies the element name, namespace, and whether the element is qualified, and whether the xsi:nil attribute is generated if the class is set to null.

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

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

[XmlRoot(Namespace="www.contoso.com",
ElementName="MyGroupName",
DataType="string",
IsNullable=true)]
public ref class Group
{
private:
   String^ groupNameValue;

public:

   // Insert code for the Group class.
   Group(){}

   Group( String^ groupNameVal )
   {
      groupNameValue = groupNameVal;
   }

   property String^ GroupName 
   {
      String^ get()
      {
         return groupNameValue;
      }
      void set( String^ value )
      {
         groupNameValue = value;
      }

   }

};

void SerializeGroup()
{
   // Create an instance of the Group class, and an
   // instance of the XmlSerializer to serialize it.
   Group^ myGroup = gcnew Group( "Redmond" );
   XmlSerializer^ ser = gcnew XmlSerializer( Group::typeid );

   // A FileStream is used to write the file.
   FileStream^ fs = gcnew FileStream( "group.xml",FileMode::Create );
   ser->Serialize( fs, myGroup );
   fs->Close();
   Console::WriteLine( myGroup->GroupName );
   Console::WriteLine( "Done" );
   Console::ReadLine();
}

int main()
{
   SerializeGroup();
}
using System;
using System.IO;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;

[XmlRoot(Namespace = "www.contoso.com",
     ElementName = "MyGroupName",
     DataType = "string",
     IsNullable=true)]
public class Group
{
    private string groupNameValue;
    // Insert code for the Group class.
    public Group()
    {
    }

    public Group(string groupNameVal)
    {
        groupNameValue = groupNameVal;
    }

    public string GroupName
    {
        get{return groupNameValue;}
        set{groupNameValue = value;}
    }
}
public class Test
{
    static void Main()
    {
        Test t = new Test();
        t.SerializeGroup();
    }

    private void SerializeGroup()
    {
        // Create an instance of the Group class, and an
        // instance of the XmlSerializer to serialize it.
        Group myGroup = new Group("Redmond");
        XmlSerializer ser = new XmlSerializer(typeof(Group));
        // A FileStream is used to write the file.
        FileStream fs = new FileStream("group.xml",FileMode.Create);
        ser.Serialize(fs,myGroup);
        fs.Close();
        Console.WriteLine(myGroup.GroupName);
        Console.WriteLine("Done");
        Console.ReadLine();
    }
}
Imports System.IO
Imports System.Xml
Imports System.Xml.Schema
Imports System.Xml.Serialization

<XmlRoot(Namespace:="www.contoso.com", _
    ElementName:="MyGroupName", _
    DataType:="string", _
    IsNullable:=True)> _
Public Class Group

    Private groupNameValue As String
    ' Insert code for the Group class.
    Public Sub New()

    End Sub

    Public Sub New(ByVal groupNameVal As String)

        groupNameValue = groupNameVal
    End Sub

    Property GroupName() As String
        Get
            Return groupNameValue
        End Get

        Set(ByVal Value As String)
            groupNameValue = Value
        End Set
    End Property
End Class

Public Class Test

    Shared Sub Main()

        Dim t As Test = New Test()
        t.SerializeGroup()
    End Sub

    Private Sub SerializeGroup()

        ' Create an instance of the Group class, and an
        ' instance of the XmlSerializer to serialize it.
        Dim myGroup As Group = New Group("Redmond")
        Dim ser As XmlSerializer = New XmlSerializer(GetType(Group))

        ' A FileStream is used to write the file.
        Dim fs As FileStream = New FileStream("group.xml", FileMode.Create)
        ser.Serialize(fs, myGroup)
        fs.Close()
        Console.WriteLine(myGroup.GroupName)
        Console.WriteLine("Done... Press any key to exit.")
        Console.ReadLine()
    End Sub

End Class

Remarks

The XmlRootAttribute 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.

You can apply the XmlRootAttribute to a class, structure, enumeration, or interface. You can also apply the attribute to the return value of an XML Web service method.

Every XML document must have a single root element that contains all the other elements. The XmlRootAttribute allows you to control how the XmlSerializer generates the root element by setting certain properties. For example, specify the name of the generated XML element by setting the ElementName property.

For more information about using attributes, see Attributes.

Note

You can use the word XmlRoot in your code instead of the longer XmlRootAttribute.

Constructors

XmlRootAttribute()

Initializes a new instance of the XmlRootAttribute class.

XmlRootAttribute(String)

Initializes a new instance of the XmlRootAttribute class and specifies the name of the XML root element.

Properties

DataType

Gets or sets the XSD data type of the XML root element.

ElementName

Gets or sets the name of the XML element that is generated and recognized by the XmlSerializer class's Serialize(TextWriter, Object) and Deserialize(Stream) methods, respectively.

IsNullable

Gets or sets a value that indicates whether the XmlSerializer must serialize a member that is set to null into the xsi:nil attribute set to true.

Namespace

Gets or sets the namespace for the XML root element.

TypeId

When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)

Methods

Equals(Object)

Returns a value that indicates whether this instance is equal to a specified object.

(Inherited from Attribute)
GetHashCode()

Returns the hash code for this instance.

(Inherited from Attribute)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute()

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.

(Inherited from Attribute)
Match(Object)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(Inherited from Attribute)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.

(Inherited from Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can be used to get the type information for an interface.

(Inherited from Attribute)
_Attribute.GetTypeInfoCount(UInt32)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).

(Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.

(Inherited from Attribute)

Applies to

See also