XmlElementAttribute 构造函数

定义

命名空间:

System.Xml.Serialization

程序集:

netstandard.dll, System.Xml.ReaderWriter.dll

初始化 XmlElementAttribute 类的新实例。

重载

名称	说明
XmlElementAttribute()	初始化 XmlElementAttribute 类的新实例。
XmlElementAttribute(String)	初始化类的新实例 XmlElementAttribute 并指定 XML 元素的名称。
XmlElementAttribute(Type)	初始化类的新实例 XmlElementAttribute ，并为应用该类的成员 XmlElementAttribute 指定类型。 序列化或反序列化包含该类型的对象时，使用此 XmlSerializer 类型。
XmlElementAttribute(String, Type)	初始化新实例并 XmlElementAttribute 指定 XML 元素的名称和应用该成员 XmlElementAttribute 的派生类型。 序列化包含该成员的对象时 XmlSerializer ，将使用此成员类型。

XmlElementAttribute()

Source:

XmlElementAttribute.cs

初始化 XmlElementAttribute 类的新实例。

public:
 XmlElementAttribute();

public XmlElementAttribute();

Public Sub New ()

示例

以下示例将应用于 XmlElementAttribute 类。

public class MyClass
{
   [XmlElement()]
   public string TeacherName;
}

Public Class MyClass1
    <XmlElement()> Public TeacherName As String
End Class

XmlElementAttribute(String)

Source:

XmlElementAttribute.cs

初始化类的新实例 XmlElementAttribute 并指定 XML 元素的名称。

public:
 XmlElementAttribute(System::String ^ elementName);

public XmlElementAttribute(string? elementName);

new System.Xml.Serialization.XmlElementAttribute : string -> System.Xml.Serialization.XmlElementAttribute

Public Sub New (elementName As String)

参数

elementName

String

序列化成员的 XML 元素名称。

示例

下面的示例演示一个简单类，其中包含名为 Vehicles 的单个字段。 该示例将应用于 XmlElementAttribute 字段并包括 elementName 参数，从而指示 XmlSerializer 生成名为“Cars”而不是“Vehicles”的 XML 元素。

public class Transportation
{
   [XmlElement("Cars")]
   public string Vehicles;
}

Public Class Transportation
    <XmlElement("Cars")> Public Vehicles As String
End Class

注解

默认情况下，序列化类实例时，该 XmlSerializer 成员名称用作 XML 元素名称。 例如，名为 Vehicle 的字段生成名为 的 VehicleXML 元素。 但是，如果需要其他元素，例如 Cars，在参数中 elementName 传递它。

XmlElementAttribute(Type)

Source:

XmlElementAttribute.cs

初始化类的新实例 XmlElementAttribute ，并为应用该类的成员 XmlElementAttribute 指定类型。 序列化或反序列化包含该类型的对象时，使用此 XmlSerializer 类型。

public:
 XmlElementAttribute(Type ^ type);

public XmlElementAttribute(Type? type);

new System.Xml.Serialization.XmlElementAttribute : Type -> System.Xml.Serialization.XmlElementAttribute

Public Sub New (type As Type)

参数

type

Type

Type派生自成员类型的对象。

示例

以下示例序列化一个名为的 Orchestra 类，该类包含一个名为的字段，该字段 Instruments返回对象数组 Instrument 。 名为 Brass 第二个类的继承自该 Instrument 类。 该示例将应用于XmlElementAttributeInstruments字段，并指定Brass类型，允许Instruments该字段接受Brass对象。 该示例还通过设置 ElementName 属性来指定 XML 元素的名称。

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

public class Orchestra
{
   public Instrument[] Instruments;
}

public class Instrument
{
   public string Name;
}

public class Brass:Instrument{
   public bool IsValved;
}

public class Run
{
    public static void Main()
    {
       Run test = new Run();
       test.SerializeObject("Override.xml");
       test.DeserializeObject("Override.xml");
    }

    public void SerializeObject(string filename)
    {
      // To write the file, a TextWriter is required.
      TextWriter writer = new StreamWriter(filename);

      XmlAttributeOverrides attrOverrides =
         new XmlAttributeOverrides();
      XmlAttributes attrs = new XmlAttributes();

      // Creates an XmlElementAttribute that overrides the Instrument type.
      XmlElementAttribute attr = new
      XmlElementAttribute(typeof(Brass));
      attr.ElementName = "Brass";

      // Adds the element to the collection of elements.
      attrs.XmlElements.Add(attr);
      attrOverrides.Add(typeof(Orchestra), "Instruments", attrs);

      // Creates the XmlSerializer using the XmlAttributeOverrides.
      XmlSerializer s =
      new XmlSerializer(typeof(Orchestra), attrOverrides);

      // Creates the object to serialize.
      Orchestra band = new Orchestra();

      // Creates an object of the derived type.
      Brass i = new Brass();
      i.Name = "Trumpet";
      i.IsValved = true;
      Instrument[] myInstruments = {i};
      band.Instruments = myInstruments;
      s.Serialize(writer,band);
      writer.Close();
   }

   public void DeserializeObject(string filename)
   {
      XmlAttributeOverrides attrOverrides =
         new XmlAttributeOverrides();
      XmlAttributes attrs = new XmlAttributes();

      // Creates an XmlElementAttribute that override the Instrument type.
      XmlElementAttribute attr = new
      XmlElementAttribute(typeof(Brass));
      attr.ElementName = "Brass";

      // Adds the element to the collection of elements.
      attrs.XmlElements.Add(attr);
      attrOverrides.Add(typeof(Orchestra), "Instruments", attrs);

      // Creates the XmlSerializer using the XmlAttributeOverrides.
      XmlSerializer s =
      new XmlSerializer(typeof(Orchestra), attrOverrides);

      FileStream fs = new FileStream(filename, FileMode.Open);
      Orchestra band = (Orchestra) s.Deserialize(fs);
      Console.WriteLine("Brass:");

      /* Deserializing differs from serializing. To read the
         derived-object values, declare an object of the derived
         type (Brass) and cast the Instrument instance to it. */
      Brass b;
      foreach(Instrument i in band.Instruments)
      {
         b= (Brass)i;
         Console.WriteLine(
         b.Name + "\n" +
         b.IsValved);
      }
   }
}

Option Strict
Option Explicit

Imports System.IO
Imports System.Xml.Serialization

Public Class Orchestra
    Public Instruments() As Instrument
End Class

Public Class Instrument
    Public Name As String
End Class

Public Class Brass
    Inherits Instrument
    Public IsValved As Boolean
End Class

Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("Override.xml")
        test.DeserializeObject("Override.xml")
    End Sub
    
    
    Public Sub SerializeObject(filename As String)
        ' To write the file, a TextWriter is required.
        Dim writer As New StreamWriter(filename)
        
        Dim attrOverrides As New XmlAttributeOverrides()
        Dim attrs As New XmlAttributes()
        
        ' Creates an XmlElementAttribute that overrides the Instrument type.
        Dim attr As New XmlElementAttribute(GetType(Brass))
        attr.ElementName = "Brass"
        
        ' Adds the element to the collection of elements.
        attrs.XmlElements.Add(attr)
        attrOverrides.Add(GetType(Orchestra), "Instruments", attrs)
        
        ' Creates the XmlSerializer using the XmlAttributeOverrides.
        Dim s As New XmlSerializer(GetType(Orchestra), attrOverrides)
        
        ' Creates the object to serialize.
        Dim band As New Orchestra()
        
        ' Creates an object of the derived type.
        Dim i As New Brass()
        i.Name = "Trumpet"
        i.IsValved = True
        Dim myInstruments() As Instrument = {i}
        band.Instruments = myInstruments
        s.Serialize(writer, band)
        writer.Close()
    End Sub
    
    
    Public Sub DeserializeObject(filename As String)
        Dim attrOverrides As New XmlAttributeOverrides()
        Dim attrs As New XmlAttributes()
        
        ' Create an XmlElementAttribute that override the Instrument type.
        Dim attr As New XmlElementAttribute(GetType(Brass))
        attr.ElementName = "Brass"
        
        ' Add the element to the collection of elements.
        attrs.XmlElements.Add(attr)
        attrOverrides.Add(GetType(Orchestra), "Instruments", attrs)
        
        ' Create the XmlSerializer using the XmlAttributeOverrides.
        Dim s As New XmlSerializer(GetType(Orchestra), attrOverrides)
        
        Dim fs As New FileStream(filename, FileMode.Open)
        Dim band As Orchestra = CType(s.Deserialize(fs), Orchestra)
        Console.WriteLine("Brass:")
        
        ' Deserializing differs from serializing. To read the
        ' derived-object values, declare an object of the derived
        ' type (Brass) and cast the Instrument instance to it. 
        Dim b As Brass
        Dim i As Instrument
        For Each i In  band.Instruments
            b = CType(i, Brass)
            Console.WriteLine((b.Name + ControlChars.Cr + b.IsValved.ToString()))
        Next i
    End Sub
End Class

注解

使用 type 参数指定派生自基类的类型。 例如，假设一个名为 MyAnimal 的属性返回一个 Animal 对象。 你想要增强该对象，以便创建一个名为 Mammal 继承自该 Animal 类的新类。 若要指示XmlSerializer在序列化MyAnimal属性时接受Mammal类，请将Mammal该类传递给Type构造函数。

XmlElementAttribute(String, Type)

Source:

XmlElementAttribute.cs

初始化新实例并 XmlElementAttribute 指定 XML 元素的名称和应用该成员 XmlElementAttribute 的派生类型。 序列化包含该成员的对象时 XmlSerializer ，将使用此成员类型。

public:
 XmlElementAttribute(System::String ^ elementName, Type ^ type);

public XmlElementAttribute(string? elementName, Type? type);

new System.Xml.Serialization.XmlElementAttribute : string * Type -> System.Xml.Serialization.XmlElementAttribute

Public Sub New (elementName As String, type As Type)

参数

elementName

String

序列化成员的 XML 元素名称。

type

Type

Type派生自成员类型的对象。

示例

以下示例序列化一个名为的 Orchestra 类，该类包含一个名为的字段，该字段 Instruments返回对象数组 Instrument 。 名为 Brass 第二个类的继承自该 Instrument 类。 该示例将应用于XmlElementAttributeInstruments字段，并指定Brass类型，允许Instruments该字段接受Brass对象。 该示例还通过设置 ElementName 属性来指定 XML 元素的名称。

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

public class Orchestra
{
   public Instrument[] Instruments;
}

public class Instrument
{
   public string Name;
}

public class Brass:Instrument{
   public bool IsValved;
}

public class Run
{
    public static void Main()
    {
       Run test = new Run();
       test.SerializeObject("Override.xml");
       test.DeserializeObject("Override.xml");
    }

    public void SerializeObject(string filename)
    {
      // To write the file, a TextWriter is required.
      TextWriter writer = new StreamWriter(filename);

      XmlAttributeOverrides attrOverrides =
         new XmlAttributeOverrides();
      XmlAttributes attrs = new XmlAttributes();

      // Creates an XmlElementAttribute that overrides the Instrument type.
      XmlElementAttribute attr = new
      XmlElementAttribute(typeof(Brass));
      attr.ElementName = "Brass";

      // Adds the element to the collection of elements.
      attrs.XmlElements.Add(attr);
      attrOverrides.Add(typeof(Orchestra), "Instruments", attrs);

      // Creates the XmlSerializer using the XmlAttributeOverrides.
      XmlSerializer s =
      new XmlSerializer(typeof(Orchestra), attrOverrides);

      // Creates the object to serialize.
      Orchestra band = new Orchestra();

      // Creates an object of the derived type.
      Brass i = new Brass();
      i.Name = "Trumpet";
      i.IsValved = true;
      Instrument[] myInstruments = {i};
      band.Instruments = myInstruments;
      s.Serialize(writer,band);
      writer.Close();
   }

   public void DeserializeObject(string filename)
   {
      XmlAttributeOverrides attrOverrides =
         new XmlAttributeOverrides();
      XmlAttributes attrs = new XmlAttributes();

      // Creates an XmlElementAttribute that override the Instrument type.
      XmlElementAttribute attr = new
      XmlElementAttribute(typeof(Brass));
      attr.ElementName = "Brass";

      // Adds the element to the collection of elements.
      attrs.XmlElements.Add(attr);
      attrOverrides.Add(typeof(Orchestra), "Instruments", attrs);

      // Creates the XmlSerializer using the XmlAttributeOverrides.
      XmlSerializer s =
      new XmlSerializer(typeof(Orchestra), attrOverrides);

      FileStream fs = new FileStream(filename, FileMode.Open);
      Orchestra band = (Orchestra) s.Deserialize(fs);
      Console.WriteLine("Brass:");

      /* Deserializing differs from serializing. To read the
         derived-object values, declare an object of the derived
         type (Brass) and cast the Instrument instance to it. */
      Brass b;
      foreach(Instrument i in band.Instruments)
      {
         b= (Brass)i;
         Console.WriteLine(
         b.Name + "\n" +
         b.IsValved);
      }
   }
}

Option Strict
Option Explicit

Imports System.IO
Imports System.Xml.Serialization

Public Class Orchestra
    Public Instruments() As Instrument
End Class

Public Class Instrument
    Public Name As String
End Class

Public Class Brass
    Inherits Instrument
    Public IsValved As Boolean
End Class

Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("Override.xml")
        test.DeserializeObject("Override.xml")
    End Sub
    
    
    Public Sub SerializeObject(filename As String)
        ' To write the file, a TextWriter is required.
        Dim writer As New StreamWriter(filename)
        
        Dim attrOverrides As New XmlAttributeOverrides()
        Dim attrs As New XmlAttributes()
        
        ' Creates an XmlElementAttribute that overrides the Instrument type.
        Dim attr As New XmlElementAttribute(GetType(Brass))
        attr.ElementName = "Brass"
        
        ' Adds the element to the collection of elements.
        attrs.XmlElements.Add(attr)
        attrOverrides.Add(GetType(Orchestra), "Instruments", attrs)
        
        ' Creates the XmlSerializer using the XmlAttributeOverrides.
        Dim s As New XmlSerializer(GetType(Orchestra), attrOverrides)
        
        ' Creates the object to serialize.
        Dim band As New Orchestra()
        
        ' Creates an object of the derived type.
        Dim i As New Brass()
        i.Name = "Trumpet"
        i.IsValved = True
        Dim myInstruments() As Instrument = {i}
        band.Instruments = myInstruments
        s.Serialize(writer, band)
        writer.Close()
    End Sub
    
    
    Public Sub DeserializeObject(filename As String)
        Dim attrOverrides As New XmlAttributeOverrides()
        Dim attrs As New XmlAttributes()
        
        ' Create an XmlElementAttribute that override the Instrument type.
        Dim attr As New XmlElementAttribute(GetType(Brass))
        attr.ElementName = "Brass"
        
        ' Add the element to the collection of elements.
        attrs.XmlElements.Add(attr)
        attrOverrides.Add(GetType(Orchestra), "Instruments", attrs)
        
        ' Create the XmlSerializer using the XmlAttributeOverrides.
        Dim s As New XmlSerializer(GetType(Orchestra), attrOverrides)
        
        Dim fs As New FileStream(filename, FileMode.Open)
        Dim band As Orchestra = CType(s.Deserialize(fs), Orchestra)
        Console.WriteLine("Brass:")
        
        ' Deserializing differs from serializing. To read the
        ' derived-object values, declare an object of the derived
        ' type (Brass) and cast the Instrument instance to it. 
        Dim b As Brass
        Dim i As Instrument
        For Each i In  band.Instruments
            b = CType(i, Brass)
            Console.WriteLine((b.Name + ControlChars.Cr + b.IsValved.ToString()))
        Next i
    End Sub
End Class

注解

默认情况下，序列化类实例时，该 XmlSerializer 成员名称用作 XML 元素名称。 例如，名为 Vehicle 的字段生成名为 的 VehicleXML 元素。 但是，如果需要其他元素，例如 Cars，在参数中 elementName 传递它。

使用 type 参数指定派生自基类的类型。 例如，假设一个名为 MyAnimal 的属性返回一个 Animal 对象。 你想要增强该对象，以便创建一个名为 Mammal 继承自该 Animal 类的新类。 若要指示XmlSerializer在序列化MyAnimal属性时接受Mammal类，请将Mammal该类传递给Type构造函数。