KnownTypeAttribute.MethodName Propriedade
Definição
Importante
Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.
Obtém o nome de um método que retorna uma lista dos tipos que devem ser reconhecidos durante a serialização ou desserialização.
public:
property System::String ^ MethodName { System::String ^ get(); };
public string MethodName { get; }
public string? MethodName { get; }
member this.MethodName : string
Public ReadOnly Property MethodName As String
Valor da propriedade
Um String que contém o nome do método no tipo definido pela KnownTypeAttribute classe .
Exemplos
O exemplo a seguir usa o methodName
parâmetro para identificar um método no tipo que contém uma matriz de Type objetos.
namespace KnownTypeAttributeExample
{
using System;
using System.Xml;
using System.Collections.Generic;
using System.Text;
using System.Runtime.Serialization;
using System.IO;
// The constructor names the method that returns an array
// of types that can be used during deserialization.
[KnownTypeAttribute("KnownTypes")]
[DataContract]
public class Employee
{
public Employee(string newFName, string newLName)
{
FirstName = newFName;
LastName = newLName;
}
[DataMember]
internal string FirstName;
[DataMember]
internal string LastName;
[DataMember]
internal int id;
[DataMember]
internal Manager Boss;
// This method returns the array of known types.
static Type[] KnownTypes()
{
return new Type[]{typeof(Manager), typeof(Employee)};
}
}
[DataContract]
public class Manager : Employee
{
// Call the base class's constructor.
public Manager(string newFName, string newLName)
: base(newFName, newLName)
{ }
[DataMember]
internal Employee[] Reports;
}
class Program
{
public static void Main()
{
try
{
Serialize("person1.xml");
Deserialize("person1.xml");
}
catch (SerializationException se)
{
Console.WriteLine("{0}: {1}",
se.Message, se.StackTrace);
}
finally
{
Console.WriteLine("Press Enter to exit....");
Console.ReadLine();
}
}
static void Serialize(string path)
{
Employee emp = new Employee("John", "Peoples");
emp.id = 3001;
Manager theBoss = new Manager("Michiyo", "Sato");
theBoss.id = 41;
emp.Boss = theBoss;
DataContractSerializer ser =
new DataContractSerializer(typeof(Employee));
FileStream fs =
new FileStream(path, FileMode.OpenOrCreate);
ser.WriteObject(fs, emp);
fs.Close();
}
static void Deserialize(string path)
{
DataContractSerializer ser =
new DataContractSerializer(typeof(Employee));
FileStream fs = new FileStream(path,
FileMode.Open);
Employee p = (Employee)ser.ReadObject(fs);
Console.WriteLine("{0} {1}, id:{2}", p.FirstName,
p.LastName, p.id);
fs.Close();
}
}
}
' The constructor names the method that returns an array
' of types that can be used during deserialization.
<KnownTypeAttribute("KnownTypes"), DataContract()> _
Public Class Employee
Public Sub New(ByVal newFName As String, ByVal newLName As String)
FirstName = newFName
LastName = newLName
End Sub
<DataMember()> _
Friend FirstName As String
<DataMember()> _
Friend LastName As String
<DataMember()> _
Friend id As Integer
<DataMember()> _
Friend Boss As Manager
' This method returns the array of known types.
Shared Function KnownTypes() As Type()
Return New Type() {GetType(Manager), GetType(Employee)}
End Function
End Class
<DataContract()> _
Public Class Manager
Inherits Employee
' Call the base class's constructor.
Public Sub New(ByVal newFName As String, ByVal newLName As String)
MyBase.New(newFName, newLName)
End Sub
<DataMember()> _
Friend Reports() As Employee
End Class
Class Program
Public Shared Sub Main()
Try
Serialize("person1.xml")
Deserialize("person1.xml")
Catch se As SerializationException
Console.WriteLine("{0}: {1}", se.Message, se.StackTrace)
Finally
Console.WriteLine("Press Enter to exit....")
Console.ReadLine()
End Try
End Sub
Shared Sub Serialize(ByVal path As String)
Dim emp As New Employee("John", "Peoples")
emp.id = 3001
Dim theBoss As New Manager("Michiyo", "Sato")
theBoss.id = 41
emp.Boss = theBoss
Dim ser As New DataContractSerializer(GetType(Employee))
Dim fs As New FileStream(path, FileMode.OpenOrCreate)
ser.WriteObject(fs, emp)
fs.Close()
End Sub
Shared Sub Deserialize(ByVal path As String)
Dim ser As New DataContractSerializer(GetType(Employee))
Dim fs As New FileStream(path, FileMode.Open)
Dim p As Employee = CType(ser.ReadObject(fs), Employee)
Console.WriteLine("{0} {1}, id:{2}", p.FirstName, p.LastName, p.id)
fs.Close()
End Sub
End Class
Comentários
O método deve existir na classe ou estrutura à qual o KnownTypeAttribute é aplicado, deve ser estático, não deve aceitar parâmetros e deve retornar uma instância de qualquer tipo que implemente a interface genérica IEnumerable<T> , como a Collection<T> classe ou uma matriz de Type objetos.
O método é chamado uma vez por domínio de aplicativo quando o contrato de dados é carregado para o tipo.