XmlArrayItemAttribute.Type 屬性

定義

命名空間:

System.Xml.Serialization

組件:

System.Xml.XmlSerializer.dll

來源:

XmlArrayItemAttribute.cs

取得或設定陣列中允許的型別。

public:
 property Type ^ Type { Type ^ get(); void set(Type ^ value); };

public Type? Type { get; set; }

member this.Type : Type with get, set

Public Property Type As Type

屬性值

Type

陣列中所允許的 Type。

範例

下列範例會序列化 物件的陣列。 傳回陣列的欄位具有兩 XmlArrayItemAttribute 個實例的屬性。 每個實例會 XmlSerializer 指示 接受 Type 陣列中指定的 。

#using <System.Xml.dll>
#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml::Serialization;

public ref class Person
{
public:
   String^ Name;
};

public ref class Manager: public Person
{
public:
   int Rank;
};

public ref class Group
{
public:

   /* The Type property instructs the XmlSerializer to accept both
      the Person and Manager types in the array. */

   [XmlArrayItem(Type=Manager::typeid),
   XmlArrayItem(Type=Person::typeid)]
   array<Person^>^Staff;
};

void SerializeOrder( String^ filename )
{
   // Creates an XmlSerializer.
   XmlSerializer^ xSer = gcnew XmlSerializer( Group::typeid );

   // Creates the Group object, and two array items.
   Group^ myGroup = gcnew Group;
   Person^ p1 = gcnew Person;
   p1->Name = "Jacki";
   Manager^ p2 = gcnew Manager;
   p2->Name = "Megan";
   p2->Rank = 2;
   array<Person^>^myStaff = {p1,p2};
   myGroup->Staff = myStaff;
   
   // Serializes the object, and closes the StreamWriter.
   TextWriter^ writer = gcnew StreamWriter( filename );
   xSer->Serialize( writer, myGroup );
}

int main()
{
   SerializeOrder( "TypeEx.xml" );
}

using System;
using System.IO;
using System.Xml.Serialization;

public class Group
{
   /* The Type property instructs the XmlSerializer to accept both
   the Person and Manager types in the array. */
   [XmlArrayItem(Type = typeof(Manager)),
   XmlArrayItem(Type=typeof(Person))]
   public Person[]Staff;
}

public class Person
{
   public string Name;
}

public class Manager:Person
{
   public int Rank;
}

public class Run
{
   public static void Main()
   {
      Run test = new Run();
      test.SerializeOrder("TypeEx.xml");
   }

   public void SerializeOrder(string filename)
   {
      // Creates an XmlSerializer.
      XmlSerializer xSer =
      new XmlSerializer(typeof(Group));

      // Creates the Group object, and two array items.
      Group myGroup = new Group();

      Person p1 = new Person();
      p1.Name = "Jacki";
      Manager p2 = new Manager();

      p2.Name = "Megan";
      p2.Rank = 2;

      Person [] myStaff = {p1,p2};
      myGroup.Staff = myStaff;

      // Serializes the object, and closes the StreamWriter.
      TextWriter writer = new StreamWriter(filename);
      xSer.Serialize(writer, myGroup);
   }
}

Imports System.IO
Imports System.Xml.Serialization



Public Class Group
    ' The Type property instructs the XmlSerializer to accept both
    ' the Person and Manager types in the array. 
    <XmlArrayItem(Type := GetType(Manager)), _
     XmlArrayItem(Type := GetType(Person))> _
    Public Staff() As Person
        
End Class


Public Class Person
    Public Name As String
End Class 


Public Class Manager
    Inherits Person
    Public Rank As Integer
End Class 


Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeOrder("TypeEx.xml")
    End Sub 
        
    
    Public Sub SerializeOrder(filename As String)
        ' Creates an XmlSerializer.
        Dim xSer As New XmlSerializer(GetType(Group))
        
        ' Creates the Group object, and two array items.
        Dim myGroup As New Group()
        
        Dim p1 As New Person()
        p1.Name = "Jacki"
        Dim p2 As New Manager()
        
        p2.Name = "Megan"
        p2.Rank = 2
        
        Dim myStaff() As Person =  {p1, p2}
        myGroup.Staff = myStaff
        
        ' Serializes the object, and closes the StreamWriter.
        Dim writer As New StreamWriter(filename)
        xSer.Serialize(writer, myGroup)
    End Sub 
End Class

備註

Type使用 屬性可指定公用欄位或公用讀取/寫入屬性值的覆寫類型。

如果欄位或屬性傳回類型的 Object 陣列，請將 的 XmlArrayItemAttribute 多個實例套用至欄位或屬性。 針對每個實例，將 Type 屬性設定為可插入陣列的物件類型。

如果陣列只包含基本類型，則不需要套用 XmlArrayItemAttribute 。 根據預設，會 XmlSerializer 針對每個值產生一系列元素，每個元素都有相同的專案名稱，但每個元素的類型會設定為 XML 架構資料類型。 例如，下列程式碼：

' Visual Basic code  
Public Class Arrays  
   Public XSDTypes ()As Object= New Object(){"one", 2, 3.0}  
End Class  
// C# code  
public class MyArray{  
   // No XmlArrayItemAttribute is applied.  
   public object[] XSDTypes= new object[]{"one", 2, 3.2};  
}  

會產生此 XML：

<?xml version="1.0" encoding="utf-8"?>  
<Arrays xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">  
  <XSDTypes>  
    <Object xsi:type="xsd:string">one</Object>  
    <Object xsi:type="xsd:int">2</Object>  
    <Object xsi:type="xsd:double">3</Object>  
  </XSDTypes>  
</Arrays>  

不過，如果您為每個基本類型指定 Type 屬性，則會使用 .NET 類型名稱產生每個值的元素名稱。 例如，此程式碼：

' Visual Basic code  
Public Class Arrays  
   <XmlArrayItem(GetType(String)), _  
   XmlArrayItem(GetType(Integer)), _  
   XmlArrayItem(GetType(Double))> _  
   Public PrimitiveTypes () As Object = New Object(){"one", 2, 3.0}  
End Class  
// C# code  
public class Arrays{  
   [XmlArrayItem(typeof(string))]  
   [XmlArrayItem(typeof(int))]  
   [XmlArrayItem(typeof(double))]  
   public object [] PrimitiveTypes = new object[]{"one", 2, 3.0};  
}  

會產生此 XML：

<?xml version="1.0" encoding="utf-8"?>  
<Arrays xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">  
  <PrimitiveTypes>  
    <string>one</string>  
    <int>2</int>  
    <double>3</double>  
  </PrimitiveTypes>  
</Arrays>