XMLSerializer例子
using System;
using System.Xml;
using System.Xml.Serialization;
using System.IO;
using System.Collections;
using System.Collections.Generic;
/* 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)]
publicclassPurchaseOrder
{
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;
[XmlArrayAttribute("ItemsList")]
public List<OrderedItem> ListItems;
}
publicclassAddress
{
/* The XmlAttribute instructs the XmlSerializer to serialize the Name
field as an XML attribute instead of an XML element (the default
behavior). */
[XmlAttribute]
publicstring 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)]
publicstring City;
public string State;
publicstring Zip;
}
publicclassOrderedItem
{
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;
}
}
publicclassTest
{
publicstaticvoid 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 =
newXmlSerializer(typeof(PurchaseOrder));
TextWriter writer = new StreamWriter(filename);
PurchaseOrder po = newPurchaseOrder();
// 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 = newOrderedItem();
i1.ItemName = "Widget S";
i1.Description = "Small widget";
i1.UnitPrice = (decimal)5.23;
i1.Quantity = 3;
i1.Calculate();
// Create an OrderedItem object.
OrderedItem i2 = newOrderedItem();
i2.ItemName = "Widget Sxxxxx";
i2.Description = "Small widget";
i2.UnitPrice = (decimal)5.213;
i2.Quantity = 3;
i2.Calculate();
po.ListItems = new List<OrderedItem>();
po.ListItems.Add(i2);
// 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 = newXmlSerializer(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);
}
foreach (OrderedItem oi in po.ListItems)
{
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 + "'");
}
}