XmlArrayItemAttribute.DataType Vlastnost
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
Získá nebo nastaví datový typ XML vygenerovaného XML elementu.
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
Hodnota vlastnosti
Datový typ definice schématu XML (XSD).
Příklady
Následující příklad serializuje třídu s názvem PurchaseOrder
. Několik instancí XmlArrayItemAttribute třídy se použije na tři členy a DataType vlastnost pro každou instanci je nastavena na typ povolený v poli.
#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
Poznámky
Následující tabulka uvádí jednoduché datové typy schématu XML s jejich ekvivalenty .NET.
U schématu base64Binary
XML a hexBinary
datových Byte typů použijte pole objektů a podle potřeby použijte vlastnost s vlastností nastavenou DataType XmlArrayItemAttribute na "base64Binary" nebo "hexBinary". U schématu time
XML a date
datových typů použijte DateTime typ a použijte XmlArrayItemAttribute ho DataType se sadou na "datum" nebo "čas".
Pro každý typ schématu XML, který je mapován na řetězec, použijte XmlArrayItemAttribute jeho DataType vlastnost nastavenou na typ schématu XML. To ale nezmění formát serializace, pouze schéma člena.
Poznámka
Vlastnost rozlišuje malá a velká písmena, takže ji musíte nastavit přesně na jeden z datových typů schématu XML.
Poznámka
Předávání binárních dat jako elementu XML je efektivnější a pak je předává jako atribut XML.
Další informace o datových typech schémat XML naleznete v dokumentu XML Konsorcium world wide web schema 2: Datové typy.
Datový typ XSD | Datový typ .NET |
---|---|
Anyuri | String |
Base64binary | Byte Pole objektů |
boolean | Boolean |
byte | SByte |
date | DateTime |
data a času. | DateTime |
decimal | Decimal |
double | Double |
ENTITY | String |
ENTITY | String |
float | Single |
gDay | String |
gMonth | String |
gMonthDay | String |
gYear | String |
gYearMonth | String |
Hexbinary | Byte Pole objektů |
ID | String |
IDREF | String |
IDREFS | String |
int | Int32 |
integer | String |
language | String |
long | Int64 |
Název | String |
Ncname | String |
negativeInteger | String |
NMTOKEN | String |
NMTOKENS | String |
normalizedString | String |
nonNegativeInteger | String |
nonPositiveInteger | String |
ZÁPIS | String |
positiveInteger | String |
QName | XmlQualifiedName |
doba trvání | String |
řetězec | String |
short | Int16 |
time | DateTime |
token | String |
unsignedByte | Byte |
unsignedInt | UInt32 |
unsignedLong | UInt64 |
unsignedShort | UInt16 |