XmlSerializer Class (System.Xml.Serialization) (2024)

Definition

public ref class XmlSerializer

public class XmlSerializer

type XmlSerializer = class

Public Class XmlSerializer

Inheritance

Object

XmlSerializer

See Also

XML Serialization with C# - Jonathan Crozier

Examples

The following example contains two main classes: PurchaseOrder and Test. The PurchaseOrder class contains information about a single purchase. The Test class contains the methods that create the purchase order, and that read the created purchase order.

#using <System.Xml.dll>#using <System.dll>using namespace System;using namespace System::Xml;using namespace System::Xml::Serialization;using namespace System::IO;ref class Address;ref class OrderedItem;/* The XmlRootAttribute allows you to set an alternate name (PurchaseOrder) of the XML element, the element namespace; by default, the XmlSerializer uses the class name. The attribute also allows you to set the XML namespace for the element. Lastly, the attribute sets the IsNullable property, which specifies whether the xsi:null attribute appears if the class instance is set to a null reference. */[XmlRootAttribute("PurchaseOrder",Namespace="http://www.cpandl.com",IsNullable=false)]public ref class PurchaseOrder{public: Address^ ShipTo; String^ OrderDate; /* The XmlArrayAttribute changes the XML element name from the default of "OrderedItems" to "Items". */ [XmlArrayAttribute("Items")] array<OrderedItem^>^OrderedItems; Decimal SubTotal; Decimal ShipCost; Decimal TotalCost;};public ref class Address{public: /* The XmlAttribute instructs the XmlSerializer to serialize the Name field as an XML attribute instead of an XML element (the default behavior). */ [XmlAttributeAttribute] String^ Name; String^ Line1; /* Setting the IsNullable property to false instructs the XmlSerializer that the XML attribute will not appear if the City field is set to a null reference. */ [XmlElementAttribute(IsNullable=false)] String^ City; String^ State; String^ Zip;};public ref class OrderedItem{public: String^ ItemName; String^ Description; Decimal UnitPrice; int Quantity; Decimal LineTotal; /* Calculate is a custom method that calculates the price per item, and stores the value in a field. */ void Calculate() { LineTotal = UnitPrice * Quantity; }};public ref class Test{public: static void main() { // Read and write purchase orders. Test^ t = gcnew Test; t->CreatePO( "po.xml" ); t->ReadPO( "po.xml" ); }private: void CreatePO( String^ filename ) { // Create an instance of the XmlSerializer class; // specify the type of object to serialize. XmlSerializer^ serializer = gcnew XmlSerializer( PurchaseOrder::typeid ); TextWriter^ writer = gcnew StreamWriter( filename ); PurchaseOrder^ po = gcnew PurchaseOrder; // Create an address to ship and bill to. Address^ billAddress = gcnew Address; billAddress->Name = "Teresa Atkinson"; billAddress->Line1 = "1 Main St."; billAddress->City = "AnyTown"; billAddress->State = "WA"; billAddress->Zip = "00000"; // Set ShipTo and BillTo to the same addressee. po->ShipTo = billAddress; po->OrderDate = System::DateTime::Now.ToLongDateString(); // Create an OrderedItem object. OrderedItem^ i1 = gcnew OrderedItem; i1->ItemName = "Widget S"; i1->Description = "Small widget"; i1->UnitPrice = (Decimal)5.23; i1->Quantity = 3; i1->Calculate(); // Insert the item into the array. array<OrderedItem^>^items = {i1}; po->OrderedItems = items; // Calculate the total cost. Decimal subTotal = Decimal(0); System::Collections::IEnumerator^ myEnum = items->GetEnumerator(); while ( myEnum->MoveNext() ) { OrderedItem^ oi = safe_cast<OrderedItem^>(myEnum->Current); subTotal = subTotal + oi->LineTotal; } po->SubTotal = subTotal; po->ShipCost = (Decimal)12.51; po->TotalCost = po->SubTotal + po->ShipCost; // Serialize the purchase order, and close the TextWriter. serializer->Serialize( writer, po ); writer->Close(); }protected: void ReadPO( String^ filename ) { // Create an instance of the XmlSerializer class; // specify the type of object to be deserialized. XmlSerializer^ serializer = gcnew XmlSerializer( PurchaseOrder::typeid ); /* If the XML document has been altered with unknown nodes or attributes, handle them with the UnknownNode and UnknownAttribute events.*/ serializer->UnknownNode += gcnew XmlNodeEventHandler( this, &Test::serializer_UnknownNode ); serializer->UnknownAttribute += gcnew XmlAttributeEventHandler( this, &Test::serializer_UnknownAttribute ); // A FileStream is needed to read the XML document. FileStream^ fs = gcnew FileStream( filename,FileMode::Open ); // Declare an object variable of the type to be deserialized. PurchaseOrder^ po; /* Use the Deserialize method to restore the object's state with data from the XML document. */ po = dynamic_cast<PurchaseOrder^>(serializer->Deserialize( fs )); // Read the order date. Console::WriteLine( "OrderDate: {0}", po->OrderDate ); // Read the shipping address. Address^ shipTo = po->ShipTo; ReadAddress( shipTo, "Ship To:" ); // Read the list of ordered items. array<OrderedItem^>^items = po->OrderedItems; Console::WriteLine( "Items to be shipped:" ); System::Collections::IEnumerator^ myEnum1 = items->GetEnumerator(); while ( myEnum1->MoveNext() ) { OrderedItem^ oi = safe_cast<OrderedItem^>(myEnum1->Current); Console::WriteLine( "\t{0}\t{1}\t{2}\t{3}\t{4}", oi->ItemName, oi->Description, oi->UnitPrice, oi->Quantity, oi->LineTotal ); } Console::WriteLine( "\t\t\t\t\t Subtotal\t{0}", po->SubTotal ); Console::WriteLine( "\t\t\t\t\t Shipping\t{0}", po->ShipCost ); Console::WriteLine( "\t\t\t\t\t Total\t\t{0}", po->TotalCost ); } void ReadAddress( Address^ a, String^ label ) { // Read the fields of the Address object. Console::WriteLine( label ); Console::WriteLine( "\t{0}", a->Name ); Console::WriteLine( "\t{0}", a->Line1 ); Console::WriteLine( "\t{0}", a->City ); Console::WriteLine( "\t{0}", a->State ); Console::WriteLine( "\t{0}", a->Zip ); Console::WriteLine(); }private: void serializer_UnknownNode( Object^ /*sender*/, XmlNodeEventArgs^ e ) { Console::WriteLine( "Unknown Node:{0}\t{1}", e->Name, e->Text ); } void serializer_UnknownAttribute( Object^ /*sender*/, XmlAttributeEventArgs^ e ) { System::Xml::XmlAttribute^ attr = e->Attr; Console::WriteLine( "Unknown attribute {0}='{1}'", attr->Name, attr->Value ); }};int main(){ Test::main();}

using System;using System.Xml;using System.Xml.Serialization;using System.IO;/* The XmlRootAttribute allows you to set an alternate name (PurchaseOrder) of the XML element, the element namespace; by default, the XmlSerializer uses the class name. The attribute also allows you to set the XML namespace for the element. Lastly, the attribute sets the IsNullable property, which specifies whether the xsi:null attribute appears if the class instance is set to a null reference. */[XmlRootAttribute("PurchaseOrder", Namespace="http://www.cpandl.com",IsNullable = false)]public class PurchaseOrder{ public Address ShipTo; public string OrderDate; /* The XmlArrayAttribute changes the XML element name from the default of "OrderedItems" to "Items". */ [XmlArrayAttribute("Items")] public OrderedItem[] OrderedItems; public decimal SubTotal; public decimal ShipCost; public decimal TotalCost;}public class Address{ /* The XmlAttribute instructs the XmlSerializer to serialize the Name field as an XML attribute instead of an XML element (the default behavior). */ [XmlAttribute] public string Name; public string Line1; /* Setting the IsNullable property to false instructs the XmlSerializer that the XML attribute will not appear if the City field is set to a null reference. */ [XmlElementAttribute(IsNullable = false)] public string City; public string State; public string Zip;}public class OrderedItem{ public string ItemName; public string Description; public decimal UnitPrice; public int Quantity; public decimal LineTotal; /* Calculate is a custom method that calculates the price per item, and stores the value in a field. */ public void Calculate() { LineTotal = UnitPrice * Quantity; }}public class Test{ public static void Main() { // Read and write purchase orders. Test t = new Test(); t.CreatePO("po.xml"); t.ReadPO("po.xml"); } private void CreatePO(string filename) { // Create an instance of the XmlSerializer class; // specify the type of object to serialize. XmlSerializer serializer = new XmlSerializer(typeof(PurchaseOrder)); TextWriter writer = new StreamWriter(filename); PurchaseOrder po=new PurchaseOrder(); // Create an address to ship and bill to. Address billAddress = new Address(); billAddress.Name = "Teresa Atkinson"; billAddress.Line1 = "1 Main St."; billAddress.City = "AnyTown"; billAddress.State = "WA"; billAddress.Zip = "00000"; // Set ShipTo and BillTo to the same addressee. po.ShipTo = billAddress; po.OrderDate = System.DateTime.Now.ToLongDateString(); // Create an OrderedItem object. OrderedItem i1 = new OrderedItem(); i1.ItemName = "Widget S"; i1.Description = "Small widget"; i1.UnitPrice = (decimal) 5.23; i1.Quantity = 3; i1.Calculate(); // Insert the item into the array. OrderedItem [] items = {i1}; po.OrderedItems = items; // Calculate the total cost. decimal subTotal = new decimal(); foreach(OrderedItem oi in items) { subTotal += oi.LineTotal; } po.SubTotal = subTotal; po.ShipCost = (decimal) 12.51; po.TotalCost = po.SubTotal + po.ShipCost; // Serialize the purchase order, and close the TextWriter. serializer.Serialize(writer, po); writer.Close(); } protected void ReadPO(string filename) { // Create an instance of the XmlSerializer class; // specify the type of object to be deserialized. XmlSerializer serializer = new XmlSerializer(typeof(PurchaseOrder)); /* If the XML document has been altered with unknown nodes or attributes, handle them with the UnknownNode and UnknownAttribute events.*/ serializer.UnknownNode+= new XmlNodeEventHandler(serializer_UnknownNode); serializer.UnknownAttribute+= new XmlAttributeEventHandler(serializer_UnknownAttribute); // A FileStream is needed to read the XML document. FileStream fs = new FileStream(filename, FileMode.Open); // Declare an object variable of the type to be deserialized. PurchaseOrder po; /* Use the Deserialize method to restore the object's state with data from the XML document. */ po = (PurchaseOrder) serializer.Deserialize(fs); // Read the order date. Console.WriteLine ("OrderDate: " + po.OrderDate); // Read the shipping address. Address shipTo = po.ShipTo; ReadAddress(shipTo, "Ship To:"); // Read the list of ordered items. OrderedItem [] items = po.OrderedItems; Console.WriteLine("Items to be shipped:"); foreach(OrderedItem oi in items) { Console.WriteLine("\t"+ oi.ItemName + "\t" + oi.Description + "\t" + oi.UnitPrice + "\t" + oi.Quantity + "\t" + oi.LineTotal); } // Read the subtotal, shipping cost, and total cost. Console.WriteLine("\t\t\t\t\t Subtotal\t" + po.SubTotal); Console.WriteLine("\t\t\t\t\t Shipping\t" + po.ShipCost); Console.WriteLine("\t\t\t\t\t Total\t\t" + po.TotalCost); } protected void ReadAddress(Address a, string label) { // Read the fields of the Address object. Console.WriteLine(label); Console.WriteLine("\t"+ a.Name ); Console.WriteLine("\t" + a.Line1); Console.WriteLine("\t" + a.City); Console.WriteLine("\t" + a.State); Console.WriteLine("\t" + a.Zip ); Console.WriteLine(); } private void serializer_UnknownNode (object sender, XmlNodeEventArgs e) { Console.WriteLine("Unknown Node:" + e.Name + "\t" + e.Text); } private void serializer_UnknownAttribute (object sender, XmlAttributeEventArgs e) { System.Xml.XmlAttribute attr = e.Attr; Console.WriteLine("Unknown attribute " + attr.Name + "='" + attr.Value + "'"); }}

Imports System.XmlImports System.Xml.SerializationImports System.IO' The XmlRootAttribute allows you to set an alternate name' (PurchaseOrder) of the XML element, the element namespace; by' default, the XmlSerializer uses the class name. The attribute' also allows you to set the XML namespace for the element. Lastly,' the attribute sets the IsNullable property, which specifies whether' the xsi:null attribute appears if the class instance is set to' a null reference. <XmlRootAttribute("PurchaseOrder", _ Namespace := "http://www.cpandl.com", IsNullable := False)> _Public Class PurchaseOrder Public ShipTo As Address Public OrderDate As String ' The XmlArrayAttribute changes the XML element name ' from the default of "OrderedItems" to "Items". <XmlArrayAttribute("Items")> _ Public OrderedItems() As OrderedItem Public SubTotal As Decimal Public ShipCost As Decimal Public TotalCost As DecimalEnd ClassPublic Class Address ' The XmlAttribute instructs the XmlSerializer to serialize the Name ' field as an XML attribute instead of an XML element (the default ' behavior). <XmlAttribute()> _ Public Name As String Public Line1 As String ' Setting the IsNullable property to false instructs the ' XmlSerializer that the XML attribute will not appear if ' the City field is set to a null reference. <XmlElementAttribute(IsNullable := False)> _ Public City As String Public State As String Public Zip As StringEnd ClassPublic Class OrderedItem Public ItemName As String Public Description As String Public UnitPrice As Decimal Public Quantity As Integer Public LineTotal As Decimal ' Calculate is a custom method that calculates the price per item, ' and stores the value in a field. Public Sub Calculate() LineTotal = UnitPrice * Quantity End SubEnd ClassPublic Class Test Public Shared Sub Main() ' Read and write purchase orders. Dim t As New Test() t.CreatePO("po.xml") t.ReadPO("po.xml") End Sub Private Sub CreatePO(filename As String) ' Create an instance of the XmlSerializer class; ' specify the type of object to serialize. Dim serializer As New XmlSerializer(GetType(PurchaseOrder)) Dim writer As New StreamWriter(filename) Dim po As New PurchaseOrder() ' Create an address to ship and bill to. Dim billAddress As New Address() billAddress.Name = "Teresa Atkinson" billAddress.Line1 = "1 Main St." billAddress.City = "AnyTown" billAddress.State = "WA" billAddress.Zip = "00000" ' Set ShipTo and BillTo to the same addressee. po.ShipTo = billAddress po.OrderDate = System.DateTime.Now.ToLongDateString() ' Create an OrderedItem object. Dim i1 As New OrderedItem() i1.ItemName = "Widget S" i1.Description = "Small widget" i1.UnitPrice = CDec(5.23) i1.Quantity = 3 i1.Calculate() ' Insert the item into the array. Dim items(0) As OrderedItem items(0) = i1 po.OrderedItems = items ' Calculate the total cost. Dim subTotal As New Decimal() Dim oi As OrderedItem For Each oi In items subTotal += oi.LineTotal Next oi po.SubTotal = subTotal po.ShipCost = CDec(12.51) po.TotalCost = po.SubTotal + po.ShipCost ' Serialize the purchase order, and close the TextWriter. serializer.Serialize(writer, po) writer.Close() End Sub Protected Sub ReadPO(filename As String) ' Create an instance of the XmlSerializer class; ' specify the type of object to be deserialized. Dim serializer As New XmlSerializer(GetType(PurchaseOrder)) ' If the XML document has been altered with unknown ' nodes or attributes, handle them with the ' UnknownNode and UnknownAttribute events. AddHandler serializer.UnknownNode, AddressOf serializer_UnknownNode AddHandler serializer.UnknownAttribute, AddressOf serializer_UnknownAttribute ' A FileStream is needed to read the XML document. Dim fs As New FileStream(filename, FileMode.Open) ' Declare an object variable of the type to be deserialized. Dim po As PurchaseOrder ' Use the Deserialize method to restore the object's state with ' data from the XML document. po = CType(serializer.Deserialize(fs), PurchaseOrder) ' Read the order date. Console.WriteLine(("OrderDate: " & po.OrderDate)) ' Read the shipping address. Dim shipTo As Address = po.ShipTo ReadAddress(shipTo, "Ship To:") ' Read the list of ordered items. Dim items As OrderedItem() = po.OrderedItems Console.WriteLine("Items to be shipped:") Dim oi As OrderedItem For Each oi In items Console.WriteLine((ControlChars.Tab & oi.ItemName & ControlChars.Tab & _ oi.Description & ControlChars.Tab & oi.UnitPrice & ControlChars.Tab & _ oi.Quantity & ControlChars.Tab & oi.LineTotal)) Next oi ' Read the subtotal, shipping cost, and total cost. Console.WriteLine(( New String(ControlChars.Tab, 5) & _ " Subtotal" & ControlChars.Tab & po.SubTotal)) Console.WriteLine(New String(ControlChars.Tab, 5) & _ " Shipping" & ControlChars.Tab & po.ShipCost ) Console.WriteLine( New String(ControlChars.Tab, 5) & _ " Total" & New String(ControlChars.Tab, 2) & po.TotalCost) End Sub Protected Sub ReadAddress(a As Address, label As String) ' Read the fields of the Address object. Console.WriteLine(label) Console.WriteLine(ControlChars.Tab & a.Name) Console.WriteLine(ControlChars.Tab & a.Line1) Console.WriteLine(ControlChars.Tab & a.City) Console.WriteLine(ControlChars.Tab & a.State) Console.WriteLine(ControlChars.Tab & a.Zip) Console.WriteLine() End Sub Private Sub serializer_UnknownNode(sender As Object, e As XmlNodeEventArgs) Console.WriteLine(("Unknown Node:" & e.Name & ControlChars.Tab & e.Text)) End Sub Private Sub serializer_UnknownAttribute(sender As Object, e As XmlAttributeEventArgs) Dim attr As System.Xml.XmlAttribute = e.Attr Console.WriteLine(("Unknown attribute " & attr.Name & "='" & attr.Value & "'")) End SubEnd Class

Remarks

For more information about this API, see Supplemental API remarks for XmlSerializer.

Constructors

Methods

Events

Applies to

Thread Safety

This type is thread safe.

See also

• XmlAttributeOverrides
• XmlAttributes
• 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)
• How to: Control Serialization of Derived Classes
• <dateTimeSerialization>Element
• <xmlSerializer> Element