XmlTextAttribute Class

Definition

Namespace:

System.Xml.Serialization

Assembly:

System.Xml.ReaderWriter.dll

Source:

XmlTextAttribute.cs

Indicates to the XmlSerializer that the member must be treated as XML text when the class that contains it is serialized or deserialized.

public ref class XmlTextAttribute : Attribute

[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter | System.AttributeTargets.Property | System.AttributeTargets.ReturnValue)]
public class XmlTextAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter | System.AttributeTargets.Property | System.AttributeTargets.ReturnValue)>]
type XmlTextAttribute = class
    inherit Attribute

Public Class XmlTextAttribute
Inherits Attribute

Inheritance

Object

Attribute

XmlTextAttribute

Attributes

AttributeUsageAttribute

Examples

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

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

public ref class Group1
{
public:

   // The XmlTextAttribute with type set to string informs the 
   // XmlSerializer that strings should be serialized as XML text.

   [XmlText(String::typeid)]
   [XmlElement(Int32::typeid)]
   [XmlElement(Double::typeid)]
   array<Object^>^All;
   Group1()
   {
      array<Object^>^temp = {321,"One",2,3.0,"Two"};
      All = temp;
   }
};

public enum class GroupType
{
   Small, Medium, Large
};

public ref class Group2
{
public:

   [XmlText(Type=GroupType::typeid)]
   GroupType Type;
};

public ref class Group3
{
public:

   [XmlText(Type=DateTime::typeid)]
   DateTime CreationTime;
   Group3()
   {
      CreationTime = DateTime::Now;
   }
};

public ref class Test
{
public:
   static void main()
   {
      Test^ t = gcnew Test;
      t->SerializeArray( "XmlText1.xml" );
      t->SerializeEnum( "XmlText2.xml" );
      t->SerializeDateTime( "XmlText3.xml" );
   }

private:
   void SerializeArray( String^ filename )
   {
      XmlSerializer^ ser = gcnew XmlSerializer( Group1::typeid );
      Group1^ myGroup1 = gcnew Group1;
      TextWriter^ writer = gcnew StreamWriter( filename );
      ser->Serialize( writer, myGroup1 );
      writer->Close();
   }

   void SerializeEnum( String^ filename )
   {
      XmlSerializer^ ser = gcnew XmlSerializer( Group2::typeid );
      Group2^ myGroup = gcnew Group2;
      myGroup->Type = GroupType::Medium;
      TextWriter^ writer = gcnew StreamWriter( filename );
      ser->Serialize( writer, myGroup );
      writer->Close();
   }

   void SerializeDateTime( String^ filename )
   {
      XmlSerializer^ ser = gcnew XmlSerializer( Group3::typeid );
      Group3^ myGroup = gcnew Group3;
      TextWriter^ writer = gcnew StreamWriter( filename );
      ser->Serialize( writer, myGroup );
      writer->Close();
   }
};

int main()
{
   Test::main();
}

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

public class Group1{
   // The XmlTextAttribute with type set to string informs the
   // XmlSerializer that strings should be serialized as XML text.
   [XmlText(typeof(string))]
   [XmlElement(typeof(int))]
   [XmlElement(typeof(double))]
   public object [] All= new object []{321, "One", 2, 3.0, "Two" };
}

public class Group2{
   [XmlText(Type = typeof(GroupType))]
   public GroupType Type;
}
public enum GroupType{
   Small,
   Medium,
   Large
}

public class Group3{
   [XmlText(Type=typeof(DateTime))]
   public DateTime CreationTime = DateTime.Now;
}

public class Test{
   static void Main(){
      Test t = new Test();
      t.SerializeArray("XmlText1.xml");
      t.SerializeEnum("XmlText2.xml");
      t.SerializeDateTime("XmlText3.xml");
   }

   private void SerializeArray(string filename){
      XmlSerializer ser = new XmlSerializer(typeof(Group1));
      Group1 myGroup1 = new Group1();

      TextWriter writer = new StreamWriter(filename);

      ser.Serialize(writer, myGroup1);
      writer.Close();
   }

   private void SerializeEnum(string filename){
      XmlSerializer ser = new XmlSerializer(typeof(Group2));
      Group2 myGroup = new Group2();
      myGroup.Type = GroupType.Medium;
      TextWriter writer = new StreamWriter(filename);

      ser.Serialize(writer, myGroup);
      writer.Close();
   }

   private void SerializeDateTime(string filename){
      XmlSerializer ser = new XmlSerializer(typeof(Group3));
      Group3 myGroup = new Group3();
      TextWriter writer = new StreamWriter(filename);

      ser.Serialize(writer, myGroup);
      writer.Close();
   }
}

Imports System.Xml.Serialization
Imports System.IO


Public Class Group1
   ' The XmlTextAttribute with type set to String informs the 
   ' XmlSerializer that strings should be serialized as XML text.
   <XmlText(GetType(String)), _
   XmlElement(GetType(integer)), _  
   XmlElement(GetType(double))> _
   public All () As Object = _
   New Object (){321, "One", 2, 3.0, "Two" }
End Class


Public Class Group2
   <XmlText(GetType(GroupType))> _
   public Type As GroupType 
End Class

Public Enum GroupType
   Small
   Medium
   Large
End Enum

Public Class Group3
   <XmlText(GetType(DateTime))> _
   Public CreationTime As DateTime = DateTime.Now
End Class

Public Class Test
   Shared Sub Main()
      Dim t As Test = New Test()
      t.SerializeArray("XmlText1.xml")
      t.SerializeEnum("XmlText2.xml")
      t.SerializeDateTime("XmlText3.xml")
   End Sub

   Private Sub SerializeArray(filename As String)
      Dim ser As XmlSerializer = New XmlSerializer(GetType(Group1))
      Dim myGroup1 As Group1 = New Group1()

      Dim writer As TextWriter = New StreamWriter(filename)

      ser.Serialize(writer, myGroup1)
      writer.Close()
   End Sub

   Private Sub SerializeEnum(filename As String)
      Dim ser As XmlSerializer = New XmlSerializer(GetType(Group2))
      Dim myGroup As Group2 = New Group2()
      myGroup.Type = GroupType.Medium
      Dim writer As TextWriter = New StreamWriter(filename)

      ser.Serialize(writer, myGroup)
      writer.Close()
   End Sub

   Private Sub SerializeDateTime(filename As String)
      Dim ser As XmlSerializer = new XmlSerializer(GetType(Group3))
      Dim myGroup As Group3 = new Group3()
      Dim writer As TextWriter = new StreamWriter(filename)

      ser.Serialize(writer, myGroup)
      writer.Close()
   End Sub
End Class

Remarks

The XmlTextAttribute belongs to a family of attributes that controls how the XmlSerializer serializes and deserializes an object (through its Serialize and Deserialize methods). For a complete list of similar attributes, see Attributes That Control XML Serialization.

Only one instance of the XmlTextAttribute class can be applied in a class.

You can apply the XmlTextAttribute to public fields and public read/write properties that return primitive and enumeration types.

You can apply the XmlTextAttribute to a field or property that returns an array of strings. You can also apply the attribute to an array of type Object but you must set the Type property to string. In that case, any strings inserted into the array are serialized as XML text.

The XmlTextAttribute can also be applied to a field that returns an XmlNode or an array of XmlNode objects.

By default, the XmlSerializer serializes a class member as an XML element. However, if you apply the XmlTextAttribute to a member, the XmlSerializer translates its value into XML text. This means that the value is encoded into the content of an XML element.

The XML Schema Definition Tool (Xsd.exe) occasionally generates the XmlTextAttribute when creating classes from an XML Schema definition (XSD) file. This occurs when the schema contains a complexType with mixed content; in that case, the corresponding class contains a member that returns a string array to which the XmlTextAttribute is applied. For example, when the Xml Schema Definition tool processes this schema:

<xs:schema attributeFormDefault="qualified" elementFormDefault="qualified" targetNamespace=""   
xmlns:xs="http://www.w3.org/2001/XMLSchema">  
  <xs:element name="LinkList" type="LinkList" />  
  <xs:complexType name="LinkList" mixed="true">  
    <xs:sequence>  
      <xs:element minOccurs="1" maxOccurs="1" name="id" type="xs:int" />  
      <xs:element minOccurs="0" maxOccurs="1" name="name" type="xs:string" />  
      <xs:element minOccurs="0" maxOccurs="1" name="next" type="LinkList" />  
    </xs:sequence>  
  </xs:complexType>  
</xs:schema>  

the following class is generated (extra spaces and remarks have been removed):

[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.42")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlRootAttribute(Namespace = "", IsNullable = false)]
public partial class LinkList
{

    private int idField;
    private string nameField;
    private LinkList nextField;
    private string[] textField;

    public int id
    {
        get
        {
            return this.idField;
        }
        set
        {
            this.idField = value;
        }
    }

    public string name
    {
        get
        {
            return this.nameField;
        }
        set
        {
            this.nameField = value;
        }
    }

    public LinkList next
    {
        get
        {
            return this.nextField;
        }
        set
        {
            this.nextField = value;
        }
    }

    [System.Xml.Serialization.XmlTextAttribute()]
    public string[] Text
    {
        get
        {
            return this.textField;
        }
        set
        {
            this.textField = value;
        }
    }
}

<System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.42"), _
 System.SerializableAttribute(), _
 System.Diagnostics.DebuggerStepThroughAttribute(), _
 System.ComponentModel.DesignerCategoryAttribute("code"), _
 System.Xml.Serialization.XmlRootAttribute([Namespace]:="", IsNullable:=False)> _
Partial Public Class LinkList
    Private idField As Integer
    Private nameField As String
    Private nextField As LinkList
    Private textField() As String
    Public Property id() As Integer
        Get
            Return Me.idField
        End Get
        Set(ByVal value As Integer)
            Me.idField = value
        End Set
    End Property
    Public Property name() As String
        Get
            Return Me.nameField
        End Get
        Set(ByVal value As String)
            Me.nameField = value
        End Set
    End Property
    Public Property [next]() As LinkList
        Get
            Return Me.nextField
        End Get
        Set(ByVal value As LinkList)
            Me.nextField = value
        End Set
    End Property
    <System.Xml.Serialization.XmlTextAttribute()> _
    Public Property Text() As String()
        Get
            Return Me.textField
        End Get
        Set(ByVal value As String())
            Me.textField = value
        End Set
    End Property
End Class

For more information about using attributes, see Attributes.

Note

You can use the word XmlText in your code instead of the longer XmlTextAttribute.

Constructors

XmlTextAttribute()	Initializes a new instance of the XmlTextAttribute class.
XmlTextAttribute(Type)	Initializes a new instance of the XmlTextAttribute class.

Properties

DataType	Gets or sets the XML Schema definition language (XSD) data type of the text generated by the XmlSerializer.
Type	Gets or sets the type of the member.
TypeId	When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute)

Methods

Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute)
GetHashCode()	Returns the hash code for this instance. (Inherited from Attribute)
GetType()	Gets the Type of the current instance. (Inherited from Object)
IsDefaultAttribute()	When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute)
Match(Object)	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

See also

• XmlAttributeOverrides
• XmlAttributes
• XmlSerializer
• XmlText
• Introducing XML Serialization
• How to: Specify an Alternate Element Name for an XML Stream
• Controlling XML Serialization Using Attributes
• Examples of XML Serialization
• XML Schema Definition Tool (Xsd.exe)