XmlArrayAttribute クラス
XmlSerializer が特定のクラス メンバを XML 要素の配列としてシリアル化する必要があることを指定します。
名前空間: System.Xml.Serialization
アセンブリ: System.Xml (system.xml.dll 内)
構文
解説
使用例
継承階層
スレッド セーフ
プラットフォーム
バージョン情報
参照
アセンブリ: System.Xml (system.xml.dll 内)
構文<AttributeUsageAttribute(AttributeTargets.Property Or AttributeTargets.Field Or AttributeTargets.Parameter Or AttributeTargets.ReturnValue, AllowMultiple:=False)> _ Public Class XmlArrayAttribute Inherits Attribute
[AttributeUsageAttribute(AttributeTargets.Property|AttributeTargets.Field|AttributeTargets.Parameter|AttributeTargets.ReturnValue, AllowMultiple=false)] public class XmlArrayAttribute : Attribute
[AttributeUsageAttribute(AttributeTargets::Property|AttributeTargets::Field|AttributeTargets::Parameter|AttributeTargets::ReturnValue, AllowMultiple=false)] public ref class XmlArrayAttribute : public Attribute
解説XmlArrayAttribute は、XmlSerializer がオブジェクトをシリアル化または逆シリアル化する方法を制御する一連の属性の 1 つです。類似する属性の完全な一覧については、「XML シリアル化を制御する属性」を参照してください。
XmlArrayAttribute は、オブジェクトの配列を返すパブリック フィールドまたは読み取り/書き込みプロパティに適用できます。これはコレクションにも適用できる他、ArrayList を返すフィールド、または IEnumerable インターフェイスを実装するオブジェクトを返す任意のフィールドにも適用できます。
クラス メンバに XmlArrayAttribute を適用すると、XmlSerializer クラスの Serialize メソッドによって、入れ子になった XML 要素のシーケンスがこのメンバから生成されます。XML スキーマ ドキュメント (.xsd ファイル) は、このような配列を complexType として示します。たとえば、シリアル化するクラスによって発注書を表す場合は、発注品目を表すオブジェクトの配列を返すパブリック フィールドに XmlArrayAttribute を適用すると、購入された品目の配列を生成できます。
複合型またはプリミティブ型のオブジェクトの配列を返すパブリック フィールドまたはプロパティにどの属性も適用されない場合は、既定では XmlSerializer が入れ子になった XML 要素のシーケンスを生成します。生成される XML 要素についてさらに詳細に制御するには、フィールドまたはプロパティに XmlArrayItemAttribute と XmlArrayAttribute を適用します。たとえば、既定では、生成される XML 要素の名前はメンバ識別子から派生します。ElementName プロパティを設定すると、生成される XML 要素名を変更できます。
指定された型の項目およびこの型から派生したすべてのクラスを含む配列をシリアル化するには、XmlArrayItemAttribute を使用してそれぞれの型を宣言する必要があります。
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使用例クラス インスタンスを複数のオブジェクト配列を含む XML ドキュメントにシリアル化する例を次に示します。XmlArrayAttribute は、XML 要素配列になるメンバに適用されます。
Option Explicit Option Strict Imports System Imports System.IO Imports System.Xml.Serialization Imports System.Xml Public Class Run Public Shared Sub Main() Dim test As New Run() test.SerializeDocument("books.xml") End Sub Public Sub SerializeDocument(ByVal filename As String) ' Creates a new XmlSerializer. Dim s As New XmlSerializer(GetType(MyRootClass)) ' Writing the file requires a StreamWriter. Dim myWriter As New StreamWriter(filename) ' Creates an instance of the class to serialize. Dim myRootClass As New MyRootClass() ' Uses a basic method of creating an XML array: Create and ' populate a string array, and assign it to the ' MyStringArray property. Dim myString() As String = {"Hello", "world", "!"} myRootClass.MyStringArray = myString ' Uses a more advanced method of creating an array: ' create instances of the Item and BookItem, where BookItem ' is derived from Item. Dim item1 As New Item() Dim item2 As New BookItem() ' Sets the objects' properties. With item1 .ItemName = "Widget1" .ItemCode = "w1" .ItemPrice = 231 .ItemQuantity = 3 End With With item2 .ItemCode = "w2" .ItemPrice = 123 .ItemQuantity = 7 .ISBN = "34982333" .Title = "Book of Widgets" .Author = "John Smith" End With ' Fills the array with the items. Dim myItems() As Item = {item1, item2} ' Set class's Items property to the array. myRootClass.Items = myItems ' Serializes the class, writes it to disk, and closes ' the TextWriter. s.Serialize(myWriter, myRootClass) myWriter.Close() End Sub End Class ' This is the class that will be serialized. Public Class MyRootClass Private myItems() As Item ' Here is a simple way to serialize the array as XML. Using the ' XmlArrayAttribute, assign an element name and namespace. The ' IsNullable property determines whether the element will be ' generated if the field is set to a null value. If set to true , ' the default, setting it to a null value will cause the XML ' xsi:null attribute to be generated. <XmlArray(ElementName := "MyStrings", _ Namespace := "http://www.cpandl.com", _ IsNullable := True)> _ Public MyStringArray() As String ' Here is a more complex example of applying an ' XmlArrayAttribute. The Items property can contain both Item ' and BookItem objects. Use the XmlArrayItemAttribute to specify ' that both types can be inserted into the array. <XmlArrayItem(ElementName := "Item", _ IsNullable := True, _ Type := GetType(Item), _ Namespace := "http://www.cpandl.com"), _ XmlArrayItem(ElementName := "BookItem", _ IsNullable := True, _ Type := GetType(BookItem), _ Namespace := "http://www.cohowinery.com"), _ XmlArray()> _ Public Property Items As Item() Get Return myItems End Get Set myItems = value End Set End Property End Class Public Class Item <XmlElement(ElementName := "OrderItem")> _ Public ItemName As String Public ItemCode As String Public ItemPrice As Decimal Public ItemQuantity As Integer End Class Public Class BookItem Inherits Item Public Title As String Public Author As String Public ISBN As String End Class
using System; using System.IO; using System.Xml.Serialization; using System.Xml; public class Run { public static void Main() { Run test = new Run(); test.SerializeDocument("books.xml"); } public void SerializeDocument(string filename) { // Creates a new XmlSerializer. XmlSerializer s = new XmlSerializer(typeof(MyRootClass)); // Writing the file requires a StreamWriter. TextWriter myWriter= new StreamWriter(filename); // Creates an instance of the class to serialize. MyRootClass myRootClass = new MyRootClass(); /* Uses a basic method of creating an XML array: Create and populate a string array, and assign it to the MyStringArray property. */ string [] myString = {"Hello", "world", "!"}; myRootClass.MyStringArray = myString; /* Uses a more advanced method of creating an array: create instances of the Item and BookItem, where BookItem is derived from Item. */ Item item1 = new Item(); BookItem item2 = new BookItem(); // Sets the objects' properties. item1.ItemName = "Widget1"; item1.ItemCode = "w1"; item1.ItemPrice = 231; item1.ItemQuantity = 3; item2.ItemCode = "w2"; item2.ItemPrice = 123; item2.ItemQuantity = 7; item2.ISBN = "34982333"; item2.Title = "Book of Widgets"; item2.Author = "John Smith"; // Fills the array with the items. Item [] myItems = {item1,item2}; // Sets the class's Items property to the array. myRootClass.Items = myItems; /* Serializes the class, writes it to disk, and closes the TextWriter. */ s.Serialize(myWriter, myRootClass); myWriter.Close(); } } // This is the class that will be serialized. public class MyRootClass { private Item [] items; /* Here is a simple way to serialize the array as XML. Using the XmlArrayAttribute, assign an element name and namespace. The IsNullable property determines whether the element will be generated if the field is set to a null value. If set to true, the default, setting it to a null value will cause the XML xsi:null attribute to be generated. */ [XmlArray(ElementName = "MyStrings", Namespace = "http://www.cpandl.com", IsNullable = true)] public string[] MyStringArray; /* Here is a more complex example of applying an XmlArrayAttribute. The Items property can contain both Item and BookItem objects. Use the XmlArrayItemAttribute to specify that both types can be inserted into the array. */ [XmlArrayItem(ElementName= "Item", IsNullable=true, Type = typeof(Item), Namespace = "http://www.cpandl.com"), XmlArrayItem(ElementName = "BookItem", IsNullable = true, Type = typeof(BookItem), Namespace = "http://www.cohowinery.com")] [XmlArray] public Item []Items { get{return items;} set{items = value;} } } public class Item{ [XmlElement(ElementName = "OrderItem")] public string ItemName; public string ItemCode; public decimal ItemPrice; public int ItemQuantity; } public class BookItem:Item { public string Title; public string Author; public string ISBN; }
#using <System.Xml.dll> #using <System.dll> using namespace System; using namespace System::IO; using namespace System::Xml::Serialization; using namespace System::Xml; public ref class Item { public: [XmlElement(ElementName="OrderItem")] String^ ItemName; String^ ItemCode; Decimal ItemPrice; int ItemQuantity; }; public ref class BookItem: public Item { public: String^ Title; String^ Author; String^ ISBN; }; // This is the class that will be serialized. public ref class MyRootClass { private: array<Item^>^items; public: /* Here is a simple way to serialize the array as XML. Using the XmlArrayAttribute, assign an element name and namespace. The IsNullable property determines whether the element will be generated if the field is set to a null value. If set to true, the default, setting it to a null value will cause the XML xsi:null attribute to be generated. */ [XmlArray(ElementName="MyStrings", Namespace="http://www.cpandl.com",IsNullable=true)] array<String^>^MyStringArray; /* Here is a more complex example of applying an XmlArrayAttribute. The Items property can contain both Item and BookItem objects. Use the XmlArrayItemAttribute to specify that both types can be inserted into the array. */ [XmlArrayItem(ElementName="Item", IsNullable=true, Type=Item::typeid, Namespace="http://www.cpandl.com"), XmlArrayItem(ElementName="BookItem", IsNullable=true, Type=BookItem::typeid, Namespace="http://www.cohowinery.com")] [XmlArray] property array<Item^>^ Items { array<Item^>^ get() { return items; } void set( array<Item^>^value ) { items = value; } } }; public ref class Run { public: void SerializeDocument( String^ filename ) { // Creates a new XmlSerializer. XmlSerializer^ s = gcnew XmlSerializer( MyRootClass::typeid ); // Writing the file requires a StreamWriter. TextWriter^ myWriter = gcnew StreamWriter( filename ); // Creates an instance of the class to serialize. MyRootClass^ myRootClass = gcnew MyRootClass; /* Uses a basic method of creating an XML array: Create and populate a string array, and assign it to the MyStringArray property. */ array<String^>^myString = {"Hello","world","!"}; myRootClass->MyStringArray = myString; /* Uses a more advanced method of creating an array: create instances of the Item and BookItem, where BookItem is derived from Item. */ Item^ item1 = gcnew Item; BookItem^ item2 = gcnew BookItem; // Sets the objects' properties. item1->ItemName = "Widget1"; item1->ItemCode = "w1"; item1->ItemPrice = 231; item1->ItemQuantity = 3; item2->ItemCode = "w2"; item2->ItemPrice = 123; item2->ItemQuantity = 7; item2->ISBN = "34982333"; item2->Title = "Book of Widgets"; item2->Author = "John Smith"; // Fills the array with the items. array<Item^>^myItems = {item1,item2}; // Sets the class's Items property to the array. myRootClass->Items = myItems; /* Serializes the class, writes it to disk, and closes the TextWriter. */ s->Serialize( myWriter, myRootClass ); myWriter->Close(); } }; int main() { Run^ test = gcnew Run; test->SerializeDocument( "books.xml" ); }
import System.*; import System.IO.*; import System.Xml.Serialization.*; import System.Xml.*; public class Run { public static void main(String[] args) { Run test = new Run(); test.SerializeDocument("books.xml"); } //main public void SerializeDocument(String fileName) { // Creates a new XmlSerializer. XmlSerializer s = new XmlSerializer(MyRootClass.class.ToType()); // Writing the file requires a StreamWriter. TextWriter myWriter = new StreamWriter(fileName); // Creates an instance of the class to serialize. MyRootClass myRootClass = new MyRootClass(); /* Uses a basic method of creating an XML array: Create and populate a string array, and assign it to the MyStringArray property. */ String myString[] = { "Hello", "world", "!" }; myRootClass.myStringArray = myString; /* Uses a more advanced method of creating an array: create instances of the Item and BookItem, where BookItem is derived from Item. */ Item item1 = new Item(); BookItem item2 = new BookItem(); // Sets the objects' properties. item1.itemName = "Widget1"; item1.itemCode = "w1"; item1.itemPrice = Convert.ToDecimal(231); item1.itemQuantity = 3; item2.itemCode = "w2"; item2.itemPrice = Convert.ToDecimal(123); item2.itemQuantity = 7; item2.isbn = "34982333"; item2.title = "Book of Widgets"; item2.author = "John Smith"; // Fills the array with the items. Item myItems[] = { item1, item2 }; // Sets the class's Items property to the array. myRootClass.set_Items(myItems); /* Serializes the class, writes it to disk, and closes the TextWriter. */ s.Serialize(myWriter, myRootClass); myWriter.Close(); } //SerializeDocument } //Run // This is the class that will be serialized. public class MyRootClass { private Item items[]; /* Here is a simple way to serialize the array as XML. Using the XmlArrayAttribute, assign an element name and namespace. The IsNullable property determines whether the element will be generated if the field is set to a null value. If set to true, the default, setting it to a null value will cause the XML xsi:null attribute to be generated. */ /** @attribute XmlArray(ElementName = "MyStrings", Namespace = "http://www.cpandl.com", IsNullable = true) */ public String myStringArray[]; /* Here is a more complex example of applying an XmlArrayAttribute. The Items property can contain both Item and BookItem objects. Use the XmlArrayItemAttribute to specify that both types can be inserted into the array. */ /** @attribute XmlArrayItem(ElementName = "Item", IsNullable = true, Type = Item.class, Namespace = "http://www.cpandl.com") @attribute XmlArrayItem(ElementName = "BookItem", IsNullable = true, Type = BookItem.class, Namespace = "http://www.cohowinery.com") */ /** @attribute XmlArray() */ /** @property */ public Item[] get_Items() { return items; } //get_Items /** @property */ public void set_Items(Item[] value) { items = value; } //set_Items } //MyRootClass public class Item { /** @attribute XmlElement(ElementName = "OrderItem") */ public String itemName; public String itemCode; public System.Decimal itemPrice; public int itemQuantity; } //Item public class BookItem extends Item { public String title; public String author; public String isbn; } //BookItem
継承階層
System.Object
System.Attribute
System.Xml.Serialization.XmlArrayAttribute
System.Attribute
System.Xml.Serialization.XmlArrayAttribute
スレッド セーフプラットフォームWindows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。
バージョン情報参照- XmlArrayAttribute クラスのページへのリンク
