XmlArrayItemAttribute XmlArrayItemAttribute XmlArrayItemAttribute XmlArrayItemAttribute Class

Definición

Representa un atributo que especifica los tipos derivados que XmlSerializer puede colocar en una matriz serializada.Represents an attribute that specifies the derived types that the XmlSerializer can place in a serialized array.

public ref class XmlArrayItemAttribute : Attribute
[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter | System.AttributeTargets.Property | System.AttributeTargets.ReturnValue, AllowMultiple=true)]
[System.AttributeUsage(System.AttributeTargets.Property | System.AttributeTargets.Field | System.AttributeTargets.Parameter | System.AttributeTargets.ReturnValue, AllowMultiple=true)]
public class XmlArrayItemAttribute : Attribute
type XmlArrayItemAttribute = class
    inherit Attribute
Public Class XmlArrayItemAttribute
Inherits Attribute
Herencia
XmlArrayItemAttributeXmlArrayItemAttributeXmlArrayItemAttributeXmlArrayItemAttribute
Atributos

Ejemplos

En el ejemplo siguiente se serializa una clase Group denominada que contiene un campo Employees denominado que devuelve una matriz Employee de objetos.The following example serializes a class named Group that contains a field named Employees that returns an array of Employee objects. XmlArrayItemAttribute En el ejemplo se aplica al campo, con lo XmlSerializer que se indica a que puede insertar objetos del tipo de clase baseEmployee() y del tipo de claseManagerderivada () en la matriz serializada.The example applies the XmlArrayItemAttribute to the field, thereby instructing the XmlSerializer that it can insert objects of both the base class (Employee) type and derived class type (Manager) into the serialized array.

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

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

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

public ref class Manager: public Employee
{
public:
   int Level;
};

public ref class Group
{
public:

   /* The XmlArrayItemAttribute allows the XmlSerializer to insert
      both the base type (Employee) and derived type (Manager) 
      into serialized arrays. */

   [XmlArrayItem(Manager::typeid),
   XmlArrayItem(Employee::typeid)]
   array<Employee^>^Employees;

   /* Use the XmlArrayItemAttribute to specify types allowed
      in an array of Object items. */

   [XmlArray]
   [XmlArrayItem(Int32::typeid,
   ElementName="MyNumber"),
   XmlArrayItem(String::typeid,
   ElementName="MyString"),
   XmlArrayItem(Manager::typeid)]
   array<Object^>^ExtraInfo;
};

void SerializeObject( String^ filename )
{
   // Creates a new XmlSerializer.
   XmlSerializer^ s = gcnew XmlSerializer( Group::typeid );

   // Writing the XML file to disk requires a TextWriter.
   TextWriter^ writer = gcnew StreamWriter( filename );
   Group^ group = gcnew Group;
   Manager^ manager = gcnew Manager;
   Employee^ emp1 = gcnew Employee;
   Employee^ emp2 = gcnew Employee;
   manager->Name = "Consuela";
   manager->Level = 3;
   emp1->Name = "Seiko";
   emp2->Name = "Martina";
   array<Employee^>^emps = {manager,emp1,emp2};
   group->Employees = emps;

   // Creates an int and a string and assigns to ExtraInfo.
   array<Object^>^temp = {43,"Extra",manager};
   group->ExtraInfo = temp;

   // Serializes the object, and closes the StreamWriter.
   s->Serialize( writer, group );
   writer->Close();
}

void DeserializeObject( String^ filename )
{
   FileStream^ fs = gcnew FileStream( filename,FileMode::Open );
   XmlSerializer^ x = gcnew XmlSerializer( Group::typeid );
   Group^ g = dynamic_cast<Group^>(x->Deserialize( fs ));
   Console::WriteLine( "Members:" );
   System::Collections::IEnumerator^ myEnum = g->Employees->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Employee^ e = safe_cast<Employee^>(myEnum->Current);
      Console::WriteLine( "\t{0}", e->Name );
   }
}

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

public class Group
{  
   /* The XmlArrayItemAttribute allows the XmlSerializer to insert
      both the base type (Employee) and derived type (Manager) 
      into serialized arrays. */

   [XmlArrayItem(typeof(Manager)),
   XmlArrayItem(typeof(Employee))]
   public Employee[] Employees;

   /* Use the XmlArrayItemAttribute to specify types allowed
      in an array of Object items. */
   [XmlArray]
   [XmlArrayItem (typeof(int),
   ElementName = "MyNumber"),
   XmlArrayItem (typeof(string),
   ElementName = "MyString"),
   XmlArrayItem(typeof(Manager))]
   public object [] ExtraInfo;
}   

public class Employee
{
   public string Name;
}

public class Manager:Employee{
   public int Level;
}

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


   public void SerializeObject(string filename)
   {
      // Creates a new XmlSerializer.
      XmlSerializer s = new XmlSerializer(typeof(Group));

      // Writing the XML file to disk requires a TextWriter.
      TextWriter writer = new StreamWriter(filename);
      Group group = new Group();
      
      Manager manager = new Manager();
      Employee emp1 = new Employee();
      Employee emp2 = new Employee();
      manager.Name = "Consuela";
      manager.Level = 3;
      emp1.Name = "Seiko";
      emp2.Name = "Martina";
      Employee [] emps = new Employee[3]{manager, emp1, emp2};
      group.Employees = emps;

      // Creates an int and a string and assigns to ExtraInfo.
      group.ExtraInfo = new Object[3]{43, "Extra", manager};

      // Serializes the object, and closes the StreamWriter.
      s.Serialize(writer, group);
      writer.Close();
   }

   public void DeserializeObject(string filename)
   {
      FileStream fs = new FileStream(filename, FileMode.Open);
      XmlSerializer x = new XmlSerializer(typeof(Group));
      Group g = (Group) x.Deserialize(fs);
      Console.WriteLine("Members:");
      
      foreach(Employee e in g.Employees) 
      {
         Console.WriteLine("\t" + e.Name);
      }
   }
}
   
Option Explicit
Option Strict

Imports System
Imports System.IO
Imports System.Xml.Serialization
Imports Microsoft.VisualBasic


Public Class Group
    ' The XmlArrayItemAttribute allows the XmlSerializer to insert
    ' both the base type (Employee) and derived type (Manager)
    ' into serialized arrays. 
    
    <XmlArrayItem(GetType(Manager)), _
     XmlArrayItem(GetType(Employee))> _
    Public Employees() As Employee
    
    ' Use the XmlArrayItemAttribute to specify types allowed
    ' in an array of Object items. 
    <XmlArray(), _
     XmlArrayItem(GetType(Integer), ElementName := "MyNumber"), _
     XmlArrayItem(GetType(String), ElementName := "MyString"), _
     XmlArrayItem(GetType(Manager))> _
    Public ExtraInfo() As Object
End Class

Public Class Employee
    Public Name As String
End Class

Public Class Manager
    Inherits Employee
    Public Level As Integer
End Class


Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("TypeDoc.xml")
        test.DeserializeObject("TypeDoc.xml")
    End Sub
    
       
    Public Sub SerializeObject(ByVal filename As String)
        ' Creates a new XmlSerializer.
        Dim s As New XmlSerializer(GetType(Group))
        
        ' Writing the XML file to disk requires a TextWriter.
        Dim writer As New StreamWriter(filename)
        Dim group As New Group()
        
        Dim manager As New Manager()
        Dim emp1 As New Employee()
        Dim emp2 As New Employee()
        manager.Name = "Consuela"
        manager.Level = 3
        emp1.Name = "Seiko"
        emp2.Name = "Martina"
        Dim emps() As Employee = {manager, emp1, emp2}
        group.Employees = emps
        
        ' Creates an int and a string and assigns to ExtraInfo.
        group.ExtraInfo = New Object() {43, "Extra", manager}
        
        ' Serializes the object, and closes the StreamWriter.
        s.Serialize(writer, group)
        writer.Close()
    End Sub
    
    
    Public Sub DeserializeObject(ByVal filename As String)
        Dim fs As New FileStream(filename, FileMode.Open)
        Dim x As New XmlSerializer(GetType(Group))
        Dim g As Group = CType(x.Deserialize(fs), Group)
        Console.WriteLine("Members:")
        
        Dim e As Employee
        For Each e In  g.Employees
            Console.WriteLine(ControlChars.Tab & e.Name)
        Next e
    End Sub
End Class

Comentarios

Pertenece a una familia de atributos que controla XmlSerializer cómo serializa o deserializa un objeto. XmlArrayItemAttributeThe XmlArrayItemAttribute belongs to a family of attributes that controls how the XmlSerializer serializes or deserializes an object. Para obtener una lista completa de atributos similares, vea atributos que controlan la serialización XML.For a complete list of similar attributes, see Attributes That Control XML Serialization.

Puede aplicar XmlArrayItemAttribute a cualquier miembro de lectura/escritura público que devuelva una matriz o que proporcione acceso a una.You can apply the XmlArrayItemAttribute to any public read/write member that returns an array, or provides access to one. Por ejemplo, un campo que devuelve una matriz de objetos, una colección, ArrayListo cualquier clase que implementa la IEnumerable interfaz.For example, a field that returns an array of objects, a collection, an ArrayList, or any class that implements the IEnumerable interface.

Admite polimorfismo; en otras palabras, XmlSerializer permite a agregar objetos derivados a una matriz. XmlArrayItemAttributeThe XmlArrayItemAttribute supports polymorphism--in other words, it allows the XmlSerializer to add derived objects to an array. Por ejemplo, supongamos que Mammal una clase denominada se deriva de una Animalclase base denominada.For example, suppose a class named Mammal is derived from a base class named Animal. Supongamos además que una MyAnimals clase denominada contiene un campo que devuelve una Animal matriz de objetos.Further suppose that a class named MyAnimals contains a field that returns an array of Animal objects. Para permitir XmlSerializer que serialice el Animal tipo y Mammal , aplique el XmlArrayItemAttribute al campo dos veces, cada vez que especifique uno de los dos tipos aceptables.To allow the XmlSerializer to serialize both the Animal and Mammal type, apply the XmlArrayItemAttribute to the field twice, each time specifying one of the two acceptable types.

Nota

Puede aplicar varias instancias de XmlArrayItemAttribute o XmlElementAttribute para especificar los tipos de objetos que se pueden insertar en la matriz.You can apply multiple instances of the XmlArrayItemAttribute or XmlElementAttribute to specify types of objects that can be inserted into the array.

Nota

No se admite la serialización de un campo o propiedad que devuelva una interfaz o matriz de interfaces.The serialization of a field or property that returns an interface or array of interfaces is not supported.

Para obtener más información sobre el uso de atributos, vea atributos.For more information about using attributes, see Attributes.

Nota

Puede usar la palabra XmlArrayItem en el código en lugar de la más larga. XmlArrayItemAttributeYou can use the word XmlArrayItem in your code instead of the longer XmlArrayItemAttribute.

Constructores

XmlArrayItemAttribute() XmlArrayItemAttribute() XmlArrayItemAttribute() XmlArrayItemAttribute()

Inicializa una nueva instancia de la clase XmlArrayItemAttribute.Initializes a new instance of the XmlArrayItemAttribute class.

XmlArrayItemAttribute(String) XmlArrayItemAttribute(String) XmlArrayItemAttribute(String) XmlArrayItemAttribute(String)

Inicializa una instancia nueva de la clase XmlArrayItemAttribute y especifica el nombre del elemento XML generado en el documento XML.Initializes a new instance of the XmlArrayItemAttribute class and specifies the name of the XML element generated in the XML document.

XmlArrayItemAttribute(String, Type) XmlArrayItemAttribute(String, Type) XmlArrayItemAttribute(String, Type) XmlArrayItemAttribute(String, Type)

Inicializa una instancia nueva de la clase XmlArrayItemAttribute y especifica el nombre del elemento XML generado en el documento XML, así como el Type que puede insertarse en el documento XML generado.Initializes a new instance of the XmlArrayItemAttribute class and specifies the name of the XML element generated in the XML document and the Type that can be inserted into the generated XML document.

XmlArrayItemAttribute(Type) XmlArrayItemAttribute(Type) XmlArrayItemAttribute(Type) XmlArrayItemAttribute(Type)

Inicializa una instancia nueva de la clase XmlArrayItemAttribute y especifica el Type que puede insertarse en la matriz serializada.Initializes a new instance of the XmlArrayItemAttribute class and specifies the Type that can be inserted into the serialized array.

Propiedades

DataType DataType DataType DataType

Obtiene o establece el tipo de datos XML del elemento XML generado.Gets or sets the XML data type of the generated XML element.

ElementName ElementName ElementName ElementName

Obtiene o establece el nombre del elemento XML generado.Gets or sets the name of the generated XML element.

Form Form Form Form

Obtiene o establece un valor que indica si el nombre del elemento XML generado está calificado.Gets or sets a value that indicates whether the name of the generated XML element is qualified.

IsNullable IsNullable IsNullable IsNullable

Obtiene o establece un valor que indica si XmlSerializer debe serializar un miembro como una etiqueta XML vacía con el atributo xsi:nil establecido en true.Gets or sets a value that indicates whether the XmlSerializer must serialize a member as an empty XML tag with the xsi:nil attribute set to true.

Namespace Namespace Namespace Namespace

Obtiene o establece el espacio de nombres del elemento XML generado.Gets or sets the namespace of the generated XML element.

NestingLevel NestingLevel NestingLevel NestingLevel

Obtiene o establece el nivel en una jerarquía de elementos XML a los que afecta XmlArrayItemAttribute.Gets or sets the level in a hierarchy of XML elements that the XmlArrayItemAttribute affects.

Type Type Type Type

Obtiene o establece el tipo permitido en una matriz.Gets or sets the type allowed in an array.

TypeId TypeId TypeId TypeId

Cuando se implementa en una clase derivada, obtiene un identificador único para este Attribute.When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)

Métodos

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Devuelve un valor que indica si esta instancia es igual que un objeto especificado.Returns a value that indicates whether this instance is equal to a specified object.

(Inherited from Attribute)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Devuelve el código hash de esta instancia.Returns the hash code for this instance.

(Inherited from Attribute)
GetType() GetType() GetType() GetType()

Obtiene el Type de la instancia actual.Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute() IsDefaultAttribute() IsDefaultAttribute() IsDefaultAttribute()

Si se reemplaza en una clase derivada, indica si el valor de esta instancia es el valor predeterminado de la clase derivada.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) Match(Object) Match(Object) Match(Object)

Cuando se invalida en una clase derivada, devuelve un valor que indica si esta instancia es igual a un objeto especificado.When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(Inherited from Attribute)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Crea una copia superficial del objeto Object actual.Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

Devuelve una cadena que representa el objeto actual.Returns a string that represents the current object.

(Inherited from Object)

Implementaciones de interfaz explícitas

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

Asigna un conjunto de nombres a un conjunto correspondiente de identificadores de envío.Maps a set of names to a corresponding set of dispatch identifiers.

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

Obtiene la información de tipos de un objeto, que puede utilizarse para obtener la información de tipos de una interfaz.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) _Attribute.GetTypeInfoCount(UInt32) _Attribute.GetTypeInfoCount(UInt32) _Attribute.GetTypeInfoCount(UInt32)

Recupera el número de interfaces de información de tipo que proporciona un objeto (0 ó 1).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) _Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr) _Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr) _Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Proporciona acceso a las propiedades y los métodos expuestos por un objeto.Provides access to properties and methods exposed by an object.

(Inherited from Attribute)

Se aplica a

Consulte también: