XmlArrayItemAttribute.DataType Proprietà

public:
 property System::String ^ DataType { System::String ^ get(); void set(System::String ^ value); };

public string DataType { get; set; }

member this.DataType : string with get, set

Public Property DataType As String

Valore della proprietà

Tipo di dati XSD (XML Schema Definition).

Esempio

Nell'esempio seguente viene serializzata una classe denominata PurchaseOrder. Diverse istanze della XmlArrayItemAttribute classe vengono applicate a tre membri e la DataType proprietà per ogni istanza viene impostata su un tipo consentito nella matrice.

using System;
using System.Collections;
using System.Xml;
using System.Xml.Serialization;
using System.IO;
using System.Xml.Schema;
public class PurchaseOrder
{
   [XmlArrayItem(DataType = "gMonth", 
   ElementName="MyMonths",
   Namespace = "http://www.cohowinery.com")]
   public string[] Months;

   [XmlArrayItem(typeof(Item)), XmlArrayItem(typeof(NewItem))]
   public Item[] Items;

   [XmlArray(IsNullable = true)]
   [XmlArrayItem(typeof(string)), 
   XmlArrayItem(typeof(double)), 
   XmlArrayItem(typeof(NewItem))]
   public object[] Things;
   }

public class Item{
   public string ItemID;
   public Item(){}
   public Item(string id){
    ItemID = id;
   }
}
public class NewItem:Item{
   public string Category;
   public NewItem(){}
   public NewItem(string id, string cat){
    this.ItemID = id;
    Category = cat;
    }
}
 
public class Test
{
   public static void Main()
   {
      // Read and write purchase orders.
      Test t = new Test();
      t.SerializeObject("ArrayItemEx.xml");
      t.DeserializeObject("ArrayItemEx.xml");
   } 

   private void SerializeObject(string filename)
   {
      // Create an instance of the XmlSerializer class;
      // specify the type of object to serialize.
      XmlSerializer serializer = 
      new XmlSerializer(typeof(PurchaseOrder));
      TextWriter writer = new StreamWriter(filename);
      // Create a PurchaseOrder and set its properties.
      PurchaseOrder po=new PurchaseOrder();
      po.Months = new string[]{ "March", "May", "August"};
      po.Items= new Item[]{new Item("a1"), new NewItem("b1", "book")};
      po.Things= new object[] {"String", 2003.31, new NewItem("Item100", "book")};
      
      // Serialize the purchase order, and close the TextWriter.
      serializer.Serialize(writer, po);
      writer.Close();
   }
 
   protected void DeserializeObject(string filename)
   {
      // Create an instance of the XmlSerializer class;
      // specify the type of object to be deserialized.
      XmlSerializer serializer = new XmlSerializer(typeof(PurchaseOrder));
   
      // A FileStream is needed to read the XML document.
      FileStream fs = new FileStream(filename, FileMode.Open);
      // Declare an object variable of the type to be deserialized.
      PurchaseOrder po;
      /* Use the Deserialize method to restore the object's state with
      data from the XML document. */
      po = (PurchaseOrder) serializer.Deserialize(fs);
      foreach(string s in po.Months)
          Console.WriteLine(s);
      foreach(Item i in po.Items)
         Console.WriteLine(i.ItemID);
      foreach(object thing in po.Things)
         Console.WriteLine(thing); 
   } 
}

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

Public Class PurchaseOrder
   <XmlArrayItem(DataType:= "gMonth", _
   ElementName:="MyMonths", _
   Namespace:= "http:'www.cohowinery.com")> _
   public Months() As String 

   <XmlArrayItem(GetType(Item)), XmlArrayItem(GetType(NewItem))> _
   public Items () As Item

   <XmlArray(IsNullable:= true), _
   XmlArrayItem(GetType(String)), _
   XmlArrayItem(GetType(double)), _
   XmlArrayItem(GetType(NewItem))> _
   public Things() As Object
End Class

Public Class Item
   public ItemID As String 

   public Sub New()
   End Sub
   
   public Sub New (id As String)
    ItemID = id
   End Sub
End Class

Public Class NewItem
   Inherits Item
   public Category As String 
   
   public Sub New()
      
   End Sub

   public Sub New(id As String , cat As String )
    me.ItemID = id
    Category = cat
   End Sub
End Class
 
Public Class Test
   Shared Sub Main()
      ' Read and write purchase orders.
      Dim t As Test = New Test()
      t.SerializeObject("ArrayItemExVB.xml")
      t.DeserializeObject("ArrayItemExVB.xml")
   End Sub 

   private Sub SerializeObject(filename As String)
      ' Create an instance of the XmlSerializer class
      ' specify the type of object to serialize.
      Dim serializer As XmlSerializer = _
      New XmlSerializer(GetType(PurchaseOrder))
      Dim writer As TextWriter = New StreamWriter(filename)
      ' Create a PurchaseOrder and set its properties.
      Dim po As PurchaseOrder =New PurchaseOrder()
      po.Months = New String() { "March", "May", "August"}
      po.Items= New Item(){New Item("a1"), New NewItem("b1", "book")}
      po.Things= New Object() {"String", 2003.31, New NewItem("Item100", "book")}
      
      ' Serialize the purchase order, and close the TextWriter.
      serializer.Serialize(writer, po)
      writer.Close()
   End Sub
 
   protected Sub DeserializeObject(filename As String)
      ' Create an instance of the XmlSerializer class
      ' specify the type of object to be deserialized.
      Dim serializer As XmlSerializer = _
      New XmlSerializer(GetType(PurchaseOrder))
   
      ' A FileStream is needed to read the XML document.
      Dim fs As FileStream = New FileStream(filename, FileMode.Open)
      ' Declare an object variable of the type to be deserialized.
      Dim po As PurchaseOrder 
      ' Use the Deserialize method to restore the object's state with
      ' data from the XML document. 
      po = CType( serializer.Deserialize(fs), PurchaseOrder)
      Dim s As String
      Dim i As Item
      Dim thing As Object
      for each s in po.Months
          Console.WriteLine(s)
      Next 
      
      for each i in po.Items
         Console.WriteLine(i.ItemID)
      Next 
      
      for each thing in po.Things
         Console.WriteLine(thing) 
      Next
   End Sub
End Class

Commenti

Nella tabella seguente sono elencati i tipi di dati semplici di XML Schema con i relativi equivalenti .NET.

Per i tipi di dati e hexBinary schema XMLbase64Binary, utilizzare una matrice di Byte oggetti e applicare un oggetto XmlArrayItemAttribute con la DataType proprietà impostata su "base64Binary" o "hexBinary", in base alle esigenze. Per xml Schema time e date tipi di dati, utilizzare il DateTime tipo e applicare XmlArrayItemAttribute con il DataType valore impostato su "date" o "time".

Per ogni tipo di XML Schema mappato a una stringa, applicare con XmlArrayItemAttribute la relativa DataType proprietà impostata sul tipo di XML Schema. Tuttavia, questo non modifica il formato di serializzazione, ma solo lo schema per il membro.

Per altre informazioni sui tipi di dati xml Schema, vedere il documento World Wide Web Consortium XML Schema Part 2: Datatypes.