XmlSerializer 類別
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
將物件序列化為 XML 文件,以及從 XML 文件將物件還原序列化。 XmlSerializer 可讓您控制如何將物件編碼為 XML。
public ref class XmlSerializer
public class XmlSerializer
type XmlSerializer = class
Public Class XmlSerializer
- 繼承
-
XmlSerializer
範例
下列範例包含兩個主要類別: PurchaseOrder
和 Test
。 類別 PurchaseOrder
包含單一購買的相關信息。 類別 Test
包含建立採購單的方法,以及讀取所建立的採購單。
#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.Xml
Imports System.Xml.Serialization
Imports 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 Decimal
End Class
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 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 String
End Class
Public 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 Sub
End Class
Public 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 Sub
End Class
備註
如需此 API 的詳細資訊,請參閱 XmlSerializer 的補充 API 備註。
建構函式
XmlSerializer() |
初始化 XmlSerializer 類別的新執行個體。 |
XmlSerializer(Type) |
初始化 XmlSerializer 類別的新執行個體,該類別可將指定型別的物件序列化為 XML 文件,並可將 XML 文件還原序列化為指定型別的物件。 |
XmlSerializer(Type, String) |
初始化 XmlSerializer 類別的新執行個體,該類別可將指定型別的物件序列化為 XML 文件,並可將 XML 文件還原序列化為指定型別的物件。 指定所有 XML 項目的預設命名空間。 |
XmlSerializer(Type, Type[]) |
初始化 XmlSerializer 類別的新執行個體,該類別可將指定型別的物件序列化為 XML 文件,並可將 XML 文件還原序列化為指定型別的物件。 如果屬性或欄位傳回陣列, |
XmlSerializer(Type, XmlAttributeOverrides) |
初始化 XmlSerializer 類別的新執行個體,該類別可將指定型別的物件序列化為 XML 文件,並可將 XML 文件還原序列化為指定型別的物件。 每個要序列化的物件本身會包含類別執行個體,這個多載可以其他類別覆寫。 |
XmlSerializer(Type, XmlAttributeOverrides, Type[], XmlRootAttribute, String) |
初始化 XmlSerializer 類別的新執行個體,該類別可將 Object 型別的物件序列化為 XML 文件執行個體,並可將 XML 文件執行個體還原序列化為 Object 型別的物件。 每個要序列化的物件本身都可包含類別的執行個體,這個多載會使用其他類別對其進行覆寫。 這個多載也會指定所有 XML 項目的預設命名空間,以及要做為 XML 根項目的類別。 |
XmlSerializer(Type, XmlAttributeOverrides, Type[], XmlRootAttribute, String, String) |
初始化 XmlSerializer 類別的新執行個體,該類別可將 Object 型別的物件序列化為 XML 文件執行個體,並可將 XML 文件執行個體還原序列化為 Object 型別的物件。 每個要序列化的物件本身都可包含類別的執行個體,這個多載會使用其他類別對其進行覆寫。 這個多載也會指定所有 XML 項目的預設命名空間,以及要做為 XML 根項目的類別。 |
XmlSerializer(Type, XmlAttributeOverrides, Type[], XmlRootAttribute, String, String, Evidence) |
已淘汰.
初始化 XmlSerializer 類別的新執行個體,該類別可將指定型別的物件序列化為 XML 文件執行個體,並可將 XML 文件執行個體還原序列化為指定型別的物件。 這個多載可讓您提供序列化或還原序列化作業期間遇到的其他型別,以及所有 XML 項目的預設命名空間、用做 XML 根項目的類別及其位置,和存取所需的認證。 |
XmlSerializer(Type, XmlRootAttribute) |
初始化 XmlSerializer 類別的新執行個體,該類別可將指定型別的物件序列化為 XML 文件,並可將 XML 文件還原序列化為指定型別的物件。 它還指定做為 XML 根項目的類別。 |
XmlSerializer(XmlTypeMapping) |
使用將一個型別對應到另一個型別的物件,初始化 XmlSerializer 類別的執行個體。 |
方法
事件
UnknownAttribute |
當還原序列化期間,XmlSerializer 遭遇未知型別的 XML 屬性時發生。 |
UnknownElement |
當還原序列化期間,XmlSerializer 遭遇未知型別的 XML 項目時發生。 |
UnknownNode |
當還原序列化期間,XmlSerializer 遭遇未知型別的 XML 節點時發生。 |
UnreferencedObject |
在 SOAP 編碼的 XML 資料流還原序列化期間,XmlSerializer 遇到未使用 (未參考) 的可辨認型別時發生。 |
適用於
執行緒安全性
此型別具備執行緒安全。