XmlChoiceIdentifierAttribute Constructors
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Initializes a new instance of the XmlChoiceIdentifierAttribute class.
XmlChoiceIdentifierAttribute() |
Initializes a new instance of the XmlChoiceIdentifierAttribute class. |
XmlChoiceIdentifierAttribute(String) |
Initializes a new instance of the XmlChoiceIdentifierAttribute class. |
Initializes a new instance of the XmlChoiceIdentifierAttribute class.
public:
XmlChoiceIdentifierAttribute();
public XmlChoiceIdentifierAttribute ();
Public Sub New ()
Examples
The following example serializes a class named Choices
that includes two fields, MyChoice
and ManyChoices
. The XmlChoiceIdentifierAttribute is applied to each field that specifies (through the MemberName property) another class member that gets or sets an enumeration that detects the member value. The MyChoice
field can be set to a single value, with a corresponding enumeration member found in the EnumType
field. The ManyChoices
field returns an array of objects. The ChoiceArray
field returns an array of enumeration values. For each array member in the ManyChoices
field, a corresponding member is found in the array returned by the ChoiceArray
field.
#using <System.dll>
#using <System.xml.dll>
using namespace System;
using namespace System::Xml;
using namespace System::Xml::Serialization;
using namespace System::IO;
[XmlType(IncludeInSchema=false)]
public enum class ItemChoiceType
{
None, Word, Number, DecimalNumber
};
public enum class MoreChoices
{
None, Item, Amount, Temp
};
public ref class Choices
{
public:
// The MyChoice field can be set to any one of
// the types below.
[XmlChoiceIdentifier("EnumType")]
[XmlElement("Word",String::typeid)]
[XmlElement("Number",Int32::typeid)]
[XmlElement("DecimalNumber",Double::typeid)]
Object^ MyChoice;
// Don't serialize this field. The EnumType field
// contains the enumeration value that corresponds
// to the MyChoice field value.
[XmlIgnore]
ItemChoiceType EnumType;
// The ManyChoices field can contain an array
// of choices. Each choice must be matched to
// an array item in the ChoiceArray field.
[XmlChoiceIdentifier("ChoiceArray")]
[XmlElement("Item",String::typeid)]
[XmlElement("Amount",Int32::typeid)]
[XmlElement("Temp",Double::typeid)]
array<Object^>^ManyChoices;
// TheChoiceArray field contains the enumeration
// values, one for each item in the ManyChoices array.
[XmlIgnore]
array<MoreChoices>^ChoiceArray;
};
void SerializeObject( String^ filename );
void DeserializeObject( String^ filename );
int main()
{
SerializeObject( "Choices.xml" );
DeserializeObject( "Choices.xml" );
}
void SerializeObject( String^ filename )
{
XmlSerializer^ mySerializer = gcnew XmlSerializer( Choices::typeid );
TextWriter^ writer = gcnew StreamWriter( filename );
Choices^ myChoices = gcnew Choices;
// Set the MyChoice field to a string. Set the
// EnumType to Word.
myChoices->MyChoice = "Book";
myChoices->EnumType = ItemChoiceType::Word;
// Populate an object array with three items, one
// of each enumeration type. Set the array to the
// ManyChoices field.
array<Object^>^strChoices = {"Food",5,98.6};
myChoices->ManyChoices = strChoices;
// For each item in the ManyChoices array, add an
// enumeration value.
array<MoreChoices>^ itmChoices = {MoreChoices::Item,MoreChoices::Amount,MoreChoices::Temp};
myChoices->ChoiceArray = itmChoices;
mySerializer->Serialize( writer, myChoices );
writer->Close();
}
void DeserializeObject( String^ filename )
{
XmlSerializer^ ser = gcnew XmlSerializer( Choices::typeid );
// A FileStream is needed to read the XML document.
FileStream^ fs = gcnew FileStream( filename,FileMode::Open );
Choices^ myChoices = safe_cast<Choices^>(ser->Deserialize( fs ));
fs->Close();
// Disambiguate the MyChoice value using the enumeration.
if ( myChoices->EnumType == ItemChoiceType::Word )
{
Console::WriteLine( "Word: {0}", myChoices->MyChoice->ToString() );
}
else
if ( myChoices->EnumType == ItemChoiceType::Number )
{
Console::WriteLine( "Number: {0}", myChoices->MyChoice->ToString() );
}
else
if ( myChoices->EnumType == ItemChoiceType::DecimalNumber )
{
Console::WriteLine( "DecimalNumber: {0}", myChoices->MyChoice->ToString() );
}
// Disambiguate the ManyChoices values using the enumerations.
for ( int i = 0; i < myChoices->ManyChoices->Length; i++ )
{
if ( myChoices->ChoiceArray[ i ] == MoreChoices::Item )
Console::WriteLine( "Item: {0}", myChoices->ManyChoices[ i ] );
else
if ( myChoices->ChoiceArray[ i ] == MoreChoices::Amount )
Console::WriteLine( "Amount: ", myChoices->ManyChoices[ i ]->ToString() );
if ( myChoices->ChoiceArray[ i ] == MoreChoices::Temp )
Console::WriteLine( "Temp: {0}", myChoices->ManyChoices[ i ]->ToString() );
}
}
using System;
using System.Xml;
using System.Xml.Serialization;
using System.IO;
public class Choices{
// The MyChoice field can be set to any one of
// the types below.
[XmlChoiceIdentifier("EnumType")]
[XmlElement("Word", typeof(string))]
[XmlElement("Number", typeof(int))]
[XmlElement("DecimalNumber", typeof(double))]
public object MyChoice;
// Don't serialize this field. The EnumType field
// contains the enumeration value that corresponds
// to the MyChoice field value.
[XmlIgnore]
public ItemChoiceType EnumType;
// The ManyChoices field can contain an array
// of choices. Each choice must be matched to
// an array item in the ChoiceArray field.
[XmlChoiceIdentifier("ChoiceArray")]
[XmlElement("Item", typeof(string))]
[XmlElement("Amount", typeof(int))]
[XmlElement("Temp", typeof(double))]
public object[] ManyChoices;
// TheChoiceArray field contains the enumeration
// values, one for each item in the ManyChoices array.
[XmlIgnore]
public MoreChoices[] ChoiceArray;
}
[XmlType(IncludeInSchema=false)]
public enum ItemChoiceType{
None,
Word,
Number,
DecimalNumber
}
public enum MoreChoices{
None,
Item,
Amount,
Temp
}
public class Test{
static void Main(){
Test t = new Test();
t.SerializeObject("Choices.xml");
t.DeserializeObject("Choices.xml");
}
private void SerializeObject(string filename){
XmlSerializer mySerializer =
new XmlSerializer(typeof(Choices));
TextWriter writer = new StreamWriter(filename);
Choices myChoices = new Choices();
// Set the MyChoice field to a string. Set the
// EnumType to Word.
myChoices.MyChoice= "Book";
myChoices.EnumType = ItemChoiceType.Word;
// Populate an object array with three items, one
// of each enumeration type. Set the array to the
// ManyChoices field.
object[] strChoices = new object[]{"Food", 5, 98.6};
myChoices.ManyChoices=strChoices;
// For each item in the ManyChoices array, add an
// enumeration value.
MoreChoices[] itmChoices = new MoreChoices[]
{MoreChoices.Item,
MoreChoices.Amount,
MoreChoices.Temp};
myChoices.ChoiceArray=itmChoices;
mySerializer.Serialize(writer, myChoices);
writer.Close();
}
private void DeserializeObject(string filename){
XmlSerializer ser = new XmlSerializer(typeof(Choices));
// A FileStream is needed to read the XML document.
FileStream fs = new FileStream(filename, FileMode.Open);
Choices myChoices = (Choices)
ser.Deserialize(fs);
fs.Close();
// Disambiguate the MyChoice value using the enumeration.
if(myChoices.EnumType == ItemChoiceType.Word){
Console.WriteLine("Word: " +
myChoices.MyChoice.ToString());
}
else if(myChoices.EnumType == ItemChoiceType.Number){
Console.WriteLine("Number: " +
myChoices.MyChoice.ToString());
}
else if(myChoices.EnumType == ItemChoiceType.DecimalNumber){
Console.WriteLine("DecimalNumber: " +
myChoices.MyChoice.ToString());
}
// Disambiguate the ManyChoices values using the enumerations.
for(int i = 0; i<myChoices.ManyChoices.Length; i++){
if(myChoices.ChoiceArray[i] == MoreChoices.Item)
Console.WriteLine("Item: " + (string) myChoices.ManyChoices[i]);
else if(myChoices.ChoiceArray[i] == MoreChoices.Amount)
Console.WriteLine("Amount: " + myChoices.ManyChoices[i].ToString());
if(myChoices.ChoiceArray[i] == MoreChoices.Temp)
Console.WriteLine("Temp: " + (string) myChoices.ManyChoices[i].ToString());
}
}
}
Imports System.Xml
Imports System.Xml.Serialization
Imports System.IO
Public Class Choices
' The MyChoice field can be set to any one of
' the types below.
<XmlChoiceIdentifier("EnumType"), _
XmlElement("Word", GetType(String)), _
XmlElement("Number", GetType(Integer)), _
XmlElement("DecimalNumber", GetType(double))> _
Public MyChoice As Object
' Don't serialize this field. The EnumType field
' contains the enumeration value that corresponds
' to the MyChoice field value.
<XmlIgnore> _
Public EnumType As ItemChoiceType
'The ManyChoices field can contain an array
' of choices. Each choice must be matched to
' an array item in the ChoiceArray field.
<XmlChoiceIdentifier("ChoiceArray"), _
XmlElement("Item", GetType(string)), _
XmlElement("Amount", GetType(Integer)), _
XmlElement("Temp", GetType(double))> _
Public ManyChoices() As Object
' TheChoiceArray field contains the enumeration
' values, one for each item in the ManyChoices array.
<XmlIgnore> _
Public ChoiceArray() As MoreChoices
End Class
<XmlType(IncludeInSchema:=false)> _
Public Enum ItemChoiceType
None
Word
Number
DecimalNumber
End Enum
<XmlType(IncludeInSchema:=false)> _
Public Enum MoreChoices
None
Item
Amount
Temp
End Enum
Public Class Test
Shared Sub Main()
Dim t As Test = New Test()
t.SerializeObject("Choices.xml")
t.DeserializeObject("Choices.xml")
End Sub
private Sub SerializeObject(filename As string)
Dim mySerializer As XmlSerializer = _
New XmlSerializer(GetType(Choices))
Dim writer As TextWriter = New StreamWriter(filename)
Dim myChoices As Choices = New Choices()
' Set the MyChoice field to a string. Set the
' EnumType to Word.
myChoices.MyChoice= "Book"
myChoices.EnumType = ItemChoiceType.Word
' Populate an object array with three items, one
' of each enumeration type. Set the array to the
' ManyChoices field.
Dim strChoices () As Object = New object(){"Food", 5, 98.6}
myChoices.ManyChoices=strChoices
' For each item in the ManyChoices array, add an
' enumeration value.
Dim itmChoices () As MoreChoices = New MoreChoices() _
{MoreChoices.Item, _
MoreChoices.Amount, _
MoreChoices.Temp}
myChoices.ChoiceArray=itmChoices
mySerializer.Serialize(writer, myChoices)
writer.Close()
End Sub
private Sub DeserializeObject(filename As string)
Dim ser As XmlSerializer = New XmlSerializer(GetType(Choices))
' A FileStream is needed to read the XML document.
Dim fs As FileStream = New FileStream(filename, FileMode.Open)
Dim myChoices As Choices = CType(ser.Deserialize(fs), Choices)
fs.Close()
' Disambiguate the MyChoice value Imports the enumeration.
if myChoices.EnumType = ItemChoiceType.Word Then
Console.WriteLine("Word: " & _
myChoices.MyChoice.ToString())
else if myChoices.EnumType = ItemChoiceType.Number Then
Console.WriteLine("Number: " & _
myChoices.MyChoice.ToString())
else if myChoices.EnumType = ItemChoiceType.DecimalNumber Then
Console.WriteLine("DecimalNumber: " & _
myChoices.MyChoice.ToString())
End If
' Disambiguate the ManyChoices values Imports the enumerations.
Dim i As Integer
for i = 0 to myChoices.ManyChoices.Length -1
if myChoices.ChoiceArray(i) = MoreChoices.Item Then
Console.WriteLine("Item: " + _
myChoices.ManyChoices(i).ToString())
else if myChoices.ChoiceArray(i) = MoreChoices.Amount Then
Console.WriteLine("Amount: " + _
myChoices.ManyChoices(i).ToString())
else if (myChoices.ChoiceArray(i) = MoreChoices.Temp)
Console.WriteLine("Temp: " + _
myChoices.ManyChoices(i).ToString())
End If
Next i
End Sub
End Class
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 2.0, 2.1 |
UWP | 10.0 |
Initializes a new instance of the XmlChoiceIdentifierAttribute class.
public:
XmlChoiceIdentifierAttribute(System::String ^ name);
public XmlChoiceIdentifierAttribute (string name);
public XmlChoiceIdentifierAttribute (string? name);
new System.Xml.Serialization.XmlChoiceIdentifierAttribute : string -> System.Xml.Serialization.XmlChoiceIdentifierAttribute
Public Sub New (name As String)
Parameters
- name
- String
The member name that returns the enumeration used to detect a choice.
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 2.0, 2.1 |
UWP | 10.0 |
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