XmlAttributes.XmlArrayItems 屬性
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
取得或設定物件集合,指定 XmlSerializer 如何序列化項目 (用來插入至公用欄位或讀取/寫入屬性所傳回的陣列)。
public:
property System::Xml::Serialization::XmlArrayItemAttributes ^ XmlArrayItems { System::Xml::Serialization::XmlArrayItemAttributes ^ get(); };
public System.Xml.Serialization.XmlArrayItemAttributes XmlArrayItems { get; }
member this.XmlArrayItems : System.Xml.Serialization.XmlArrayItemAttributes
Public ReadOnly Property XmlArrayItems As XmlArrayItemAttributes
屬性值
包含 XmlArrayItemAttributes 物件集合的 XmlArrayItemAttribute 物件。
範例
下列範例會序列化類別,其中包含名為 Members
的欄位,該欄位會傳回 物件的陣列。 會建立兩 XmlArrayItemAttribute 個 物件,以允許欄位接受衍生自名為 Member
之基類的物件。 每個 物件都會透過 XmlArrayItems 屬性新增至 XmlAttributes 。
#using <System.Xml.dll>
#using <System.dll>
using namespace System;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Serialization;
public ref class Member
{
public:
String^ MemberName;
};
// This is the class that will be serialized.
public ref class Group
{
public:
array<Member^>^Members;
};
public ref class NewMember: public Member
{
public:
int MemberID;
};
public ref class RetiredMember: public NewMember
{
public:
DateTime RetireDate;
};
// Return an XmlSerializer used for overriding.
XmlSerializer^ CreateOverrider()
{
// Create XmlAttributeOverrides and XmlAttributes objects.
XmlAttributeOverrides^ xOver = gcnew XmlAttributeOverrides;
XmlAttributes^ xAttrs = gcnew XmlAttributes;
// Add an override for the XmlArrayItem.
XmlArrayItemAttribute^ xArrayItem = gcnew XmlArrayItemAttribute( NewMember::typeid );
xArrayItem->Namespace = "http://www.cpandl.com";
xAttrs->XmlArrayItems->Add( xArrayItem );
// Add a second override.
XmlArrayItemAttribute^ xArrayItem2 = gcnew XmlArrayItemAttribute( RetiredMember::typeid );
xArrayItem2->Namespace = "http://www.cpandl.com";
xAttrs->XmlArrayItems->Add( xArrayItem2 );
// Add all overrides to XmlAttribueOverrides object.
xOver->Add( Group::typeid, "Members", xAttrs );
// Create the XmlSerializer and return it.
return gcnew XmlSerializer( Group::typeid,xOver );
}
void SerializeObject( String^ filename )
{
// Create an instance of the XmlSerializer class.
XmlSerializer^ mySerializer = CreateOverrider();
// Writing the file requires a TextWriter.
TextWriter^ writer = gcnew StreamWriter( filename );
// Create an instance of the class that will be serialized.
Group^ myGroup = gcnew Group;
// Set the object properties.
NewMember^ m = gcnew NewMember;
m->MemberName = "Paul";
m->MemberID = 2;
// Create a second member.
RetiredMember^ m2 = gcnew RetiredMember;
m2->MemberName = "Renaldo";
m2->MemberID = 23;
m2->RetireDate = DateTime(2000,10,10);
array<Member^>^temp = {m,m2};
myGroup->Members = temp;
// Serialize the class, and close the TextWriter.
mySerializer->Serialize( writer, myGroup );
writer->Close();
}
void DeserializeObject( String^ filename )
{
XmlSerializer^ mySerializer = CreateOverrider();
FileStream^ fs = gcnew FileStream( filename,FileMode::Open );
Group^ myGroup = dynamic_cast<Group^>(mySerializer->Deserialize( fs ));
System::Collections::IEnumerator^ myEnum = myGroup->Members->GetEnumerator();
while ( myEnum->MoveNext() )
{
Member^ m = safe_cast<Member^>(myEnum->Current);
Console::WriteLine( m->MemberName );
}
}
int main()
{
SerializeObject( "OverrideArrayItem.xml" );
DeserializeObject( "OverrideArrayItem.xml" );
}
using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
// This is the class that will be serialized.
public class Group
{
public Member [] Members;
}
public class Member
{
public string MemberName;
}
public class NewMember:Member
{
public int MemberID;
}
public class RetiredMember:NewMember
{
public DateTime RetireDate;
}
public class Run
{
public static void Main()
{
Run test = new Run();
test.SerializeObject("OverrideArrayItem.xml");
test.DeserializeObject("OverrideArrayItem.xml");
}
// Return an XmlSerializer used for overriding.
public XmlSerializer CreateOverrider()
{
// Create XmlAttributeOverrides and XmlAttributes objects.
XmlAttributeOverrides xOver = new XmlAttributeOverrides();
XmlAttributes xAttrs = new XmlAttributes();
// Add an override for the XmlArrayItem.
XmlArrayItemAttribute xArrayItem =
new XmlArrayItemAttribute(typeof(NewMember));
xArrayItem.Namespace = "http://www.cpandl.com";
xAttrs.XmlArrayItems.Add(xArrayItem);
// Add a second override.
XmlArrayItemAttribute xArrayItem2 =
new XmlArrayItemAttribute(typeof(RetiredMember));
xArrayItem2.Namespace = "http://www.cpandl.com";
xAttrs.XmlArrayItems.Add(xArrayItem2);
// Add all overrides to XmlAttribueOverrides object.
xOver.Add(typeof(Group), "Members", xAttrs);
// Create the XmlSerializer and return it.
return new XmlSerializer(typeof(Group), xOver);
}
public void SerializeObject(string filename)
{
// Create an instance of the XmlSerializer class.
XmlSerializer mySerializer = CreateOverrider();
// Writing the file requires a TextWriter.
TextWriter writer = new StreamWriter(filename);
// Create an instance of the class that will be serialized.
Group myGroup = new Group();
// Set the object properties.
NewMember m = new NewMember();
m.MemberName = "Paul";
m.MemberID = 2;
// Create a second member.
RetiredMember m2 = new RetiredMember();
m2.MemberName = "Renaldo";
m2.MemberID = 23;
m2.RetireDate = new DateTime(2000, 10,10);
myGroup.Members = new Member[2] {m, m2};
// Serialize the class, and close the TextWriter.
mySerializer.Serialize(writer, myGroup);
writer.Close();
}
public void DeserializeObject(string filename)
{
XmlSerializer mySerializer = CreateOverrider();
FileStream fs = new FileStream(filename, FileMode.Open);
Group myGroup = (Group)
mySerializer.Deserialize(fs);
foreach(Member m in myGroup.Members)
{
Console.WriteLine(m.MemberName);
}
}
}
Imports System.IO
Imports System.Xml
Imports System.Xml.Serialization
' This is the class that will be serialized.
Public Class Group
Public Members() As Member
End Class
Public Class Member
Public MemberName As String
End Class
Public Class NewMember
Inherits Member
Public MemberID As Integer
End Class
Public Class RetiredMember
Inherits NewMember
Public RetireDate As DateTime
End Class
Public Class Run
Public Shared Sub Main()
Dim test As New Run()
test.SerializeObject("OverrideArrayItem.xml")
test.DeserializeObject("OverrideArrayItem.xml")
End Sub
' Return an XmlSerializer used for overriding.
Public Function CreateOverrider() As XmlSerializer
' Create XmlAttributeOverrides and XmlAttributes objects.
Dim xOver As New XmlAttributeOverrides()
Dim xAttrs As New XmlAttributes()
' Add an override for the XmlArrayItem.
Dim xArrayItem As New XmlArrayItemAttribute(GetType(NewMember))
xArrayItem.Namespace = "http://www.cpandl.com"
xAttrs.XmlArrayItems.Add(xArrayItem)
' Add a second override.
Dim xArrayItem2 As New XmlArrayItemAttribute(GetType(RetiredMember))
xArrayItem2.Namespace = "http://www.cpandl.com"
xAttrs.XmlArrayItems.Add(xArrayItem2)
' Add all overrides to XmlAttribueOverrides object.
xOver.Add(GetType(Group), "Members", xAttrs)
' Create the XmlSerializer and return it.
Return New XmlSerializer(GetType(Group), xOver)
End Function
Public Sub SerializeObject(ByVal filename As String)
' Create an instance of the XmlSerializer class.
Dim mySerializer As XmlSerializer = CreateOverrider()
' Writing the file requires a TextWriter.
Dim writer As New StreamWriter(filename)
' Create an instance of the class that will be serialized.
Dim myGroup As New Group()
' Set the object properties.
Dim m As New NewMember()
m.MemberName = "Paul"
m.MemberID = 2
' Create a second member.
Dim m2 As New RetiredMember()
m2.MemberName = "Renaldo"
m2.MemberID = 23
m2.RetireDate = New DateTime(2000, 10, 10)
myGroup.Members = New Member(1) {m, m2}
' Serialize the class, and close the TextWriter.
mySerializer.Serialize(writer, myGroup)
writer.Close()
End Sub
Public Sub DeserializeObject(ByVal filename As String)
Dim mySerializer As XmlSerializer = CreateOverrider()
Dim fs As New FileStream(filename, FileMode.Open)
Dim myGroup As Group = CType(mySerializer.Deserialize(fs), Group)
Dim m As Member
For Each m In myGroup.Members
Console.WriteLine(m.MemberName)
Next m
End Sub
End Class
備註
屬性 XmlArrayItems 可讓您指定可插入公用欄位或公用讀取/寫入屬性所傳回陣列的衍生型別。 針對您想要讓欄位或屬性接受的每個新類型,請建立 XmlArrayItemAttribute 物件,並將 Add 它建立至 XmlArrayItemAttributes 屬性所 XmlArrayItems 傳回的) 。 (新的型別必須衍生自欄位或 property 已經接受的類型。) Add XmlAttributes 物件到 XmlAttributeOverrides 物件,並指定包含欄位或屬性的物件類型,以及欄位或屬性的名稱。 XmlSerializer在呼叫 Serialize 或 Deserialize 方法之前, XmlAttributeOverrides 使用 物件建構 。