XmlArrayItemAttribute.DataType Property

Definition

Namespace:

System.Xml.Serialization

Assembly:

System.Xml.XmlSerializer.dll

Source:

XmlArrayItemAttribute.cs

Gets or sets the XML data type of the generated XML element.

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

Property Value

String

An XML schema definition (XSD) data type.

Examples

The following example serializes a class named PurchaseOrder. Several instances of the XmlArrayItemAttribute class are applied to three members, and the DataType property for each instance is set to a type allowed in the array.

#using <System.dll>
#using <System.xml.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Xml;
using namespace System::Xml::Serialization;
using namespace System::IO;
using namespace System::Xml::Schema;
public ref class Item
{
public:
   String^ ItemID;
   Item(){}

   Item( String^ id )
   {
      ItemID = id;
   }
};

public ref class NewItem: public Item
{
public:
   String^ Category;
   NewItem(){}

   NewItem( String^ id, String^ cat )
   {
      ItemID = id;
      Category = cat;
   }
};

public ref class PurchaseOrder
{
public:

   [XmlArrayItem(DataType="gMonth",
   ElementName="MyMonths",
   Namespace="http://www.cohowinery.com")]
   array<String^>^Months;

   [XmlArrayItem(Item::typeid),XmlArrayItem(NewItem::typeid)]
   array<Item^>^Items;

   [XmlArray(IsNullable=true)]
   [XmlArrayItem(String::typeid),
   XmlArrayItem(Double::typeid),
   XmlArrayItem(NewItem::typeid)]
   array<Object^>^Things;
};

void SerializeObject( String^ filename )
{
   // Create an instance of the XmlSerializer class;
   // specify the type of object to serialize.
   XmlSerializer^ serializer = gcnew XmlSerializer( PurchaseOrder::typeid );
   TextWriter^ writer = gcnew StreamWriter( filename );

   // Create a PurchaseOrder and set its properties.
   PurchaseOrder^ po = gcnew PurchaseOrder;
   array<String^>^months = {"March","May","August"};
   po->Months = months;
   array<Item^>^items = {gcnew Item( "a1" ),gcnew NewItem( "b1","book" )};
   po->Items = items;
   array<Object^>^things = {"String",2003.31,gcnew NewItem( "Item100","book" )};
   po->Things = things;

   // Serialize the purchase order, and close the TextWriter.
   serializer->Serialize( writer, po );
   writer->Close();
}

void DeserializeObject( String^ filename )
{
   // Create an instance of the XmlSerializer class;
   // specify the type of object to be deserialized.
   XmlSerializer^ serializer = gcnew XmlSerializer( PurchaseOrder::typeid );

   // A FileStream is needed to read the XML document.
   FileStream^ fs = gcnew 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 = safe_cast<PurchaseOrder^>(serializer->Deserialize( fs ));
   for ( int i = 0; i < po->Months->Length; ++i )
      Console::WriteLine( po->Months[ i ] );
   for ( int i = 0; i < po->Items->Length; ++i )
      Console::WriteLine( po->Items[ i ]->ItemID );
   for ( int i = 0; i < po->Things->Length; ++i )
      Console::WriteLine( po->Things[ i ] );
}

int main()
{
   // Read and write purchase orders.
   SerializeObject(  "ArrayItemEx.xml" );
   DeserializeObject(  "ArrayItemEx.xml" );
}

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

Remarks

The following table lists the XML Schema simple data types with their .NET equivalents.

For the XML Schema base64Binary and hexBinary data types, use an array of Byte objects, and apply an XmlArrayItemAttribute with the DataType property set to "base64Binary" or "hexBinary", as appropriate. For the XML Schema time and date data types, use the DateTime type and apply the XmlArrayItemAttribute with the DataType set to "date" or "time".

For every XML Schema type that is mapped to a string, apply the XmlArrayItemAttribute with its DataType property set to the XML Schema type. However, this does not change the serialization format, only the schema for the member.

Note

The property is case-sensitive, so you must set it exactly to one of the XML Schema data types.

Note

Passing binary data as an XML element is more efficient then passing it as an XML attribute.

For more information about XML Schema data types, see the World Wide Web Consortium document XML Schema Part 2: Datatypes.

XSD data type	.NET data type
anyURI	String
base64Binary	Array of Byte objects
boolean	Boolean
byte	SByte
date	DateTime
dateTime	DateTime
decimal	Decimal
double	Double
ENTITY	String
ENTITIES	String
float	Single
gDay	String
gMonth	String
gMonthDay	String
gYear	String
gYearMonth	String
hexBinary	Array of Byte objects
ID	String
IDREF	String
IDREFS	String
int	Int32
integer	String
language	String
long	Int64
Name	String
NCName	String
negativeInteger	String
NMTOKEN	String
NMTOKENS	String
normalizedString	String
nonNegativeInteger	String
nonPositiveInteger	String
NOTATION	String
positiveInteger	String
QName	XmlQualifiedName
duration	String
string	String
short	Int16
time	DateTime
token	String
unsignedByte	Byte
unsignedInt	UInt32
unsignedLong	UInt64
unsignedShort	UInt16