XmlRootAttribute Class


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

Namespace:   System.Xml.Serialization
Assembly:  System.Xml (in System.Xml.dll)


[AttributeUsageAttribute(AttributeTargets.Class | AttributeTargets.Struct | AttributeTargets.Enum | AttributeTargets.Interface | AttributeTargets.ReturnValue)]
public class XmlRootAttribute : Attribute


Initializes a new instance of the XmlRootAttribute class.


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


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


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


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.


Gets or sets the namespace for the XML root element.


When implemented in a derived class, gets a unique identifier for this Attribute.(Inherited from Attribute.)


This API supports the product infrastructure and is not intended to be used directly from your code. Returns a value that indicates whether this instance is equal to a specified object.(Inherited from Attribute.)


Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)


Returns the hash code for this instance.(Inherited from Attribute.)


Gets the Type of the current instance.(Inherited from Object.)


When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.(Inherited from Attribute.)


When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.(Inherited from Attribute.)


Creates a shallow copy of the current Object.(Inherited from Object.)


Returns a string that represents the current object.(Inherited from Object.)

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

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_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.)


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

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.(Inherited from Attribute.)

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 Extending Metadata Using Attributes.


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

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

[XmlRoot(Namespace = "www.contoso.com", 
     ElementName = "MyGroupName", 
     DataType = "string", 
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();

    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);

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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