序列化(M04)_Binary VS XML

序列化是一種轉換記憶體的物件資料格式技術，目的在於將物件資料轉換成可以保存於檔案或其他儲存位置的技術，方便未來將物件資料保存或傳送。

• 跨AppDomain時使用
  

何謂序列化與反序列化
序列化技術同時也包含反序列化方法，當物件資料序列化成資料串流(Stream)格式，藉由網路送到其他位置時，需使用反序列化的方法將之還原成物件方能繼續使用物件

.NET相關序列化技術
1、Binary Serialization

• 提供物件的完整型別保存，通常用鄉跨不同應用程式之間的物件交換ex:剪貼簿可將物件序列化後放進剪貼簿，就像應用程式關閉，也可從剪貼簿反序列化到另一個應用程式使用。
• 將物件序列化之後可以轉換到 資料串流、硬體或記憶體，透過網路就可和各應用程式交換資料。ex:Romoting技術就是依靠序列化技術完成遠端呼叫的資料傳遞。

Binary Serialization實作
(1)建立一個可序列化的類別

• 套用Serializable Attribute
• 套用NonSerialized Attribute

(2)序列化及反序列化物件

• System.Runtime.Serialization.Formatters.Binary
• 使用Formatter物件
• 使用Stream物件
• 呼叫Serialize與Deserialize方法
  

Imports System.Runtime.Serialization.Formatters.binary
Imports System.IO

Public Class BinaryClass
Private Name As String = "Jerry"
Private Age As Integer = 10
Private Birthday As Date

Public Property strName() As String
Get
Return Name
End Get
Set(ByVal value As String)
Name = value
End Set
End Property

Public Property intAge() As Integer
Get
Return Age
End Get
Set(ByVal value As Integer)
Age = value
End Set
End Property

Public Property dateBirthday() As DateTime
Get
Return Birthday
End Get
Set(ByVal value As DateTime)
Birthday = value
End Set
End Property
End Class

=====================
Imports System.Runtime.Serialization.Formatters.Binary
Imports System.IO

Public Class Form1
'1、建立物件及使用物件
Dim People As New BinaryClass()
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

People.strName = "Jerry"
People.intAge = 18
People.dateBirthday = "2009/09/15"

'2、將序列化成Binary檔案
Dim formatter As New BinaryFormatter()
Dim fs As New FileStream(Application.StartupPath & "People.bin", FileMode.Create)
formatter.Serialize(fs, People)
fs.Close()
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'3、反序列化為物件
Dim formatter As New BinaryFormatter
Dim fs As New FileStream(Application.StartupPath & "People.bin", FileMode.Open)
Dim obj As BinaryClass = CType(formatter.Deserialize(fs), BinaryClass)
fs.Close()
Messagebox.Show("Deserialize OK...Private strName" & obj.strName)
'MessageBox.Show(Application.StartupPath & "People.bin")
End Sub
End Class
========================================
2、XML Serialization

• 只保存物件當中Public的成員資料與成員屬性，不保證資料完整性，通常應用在單純的資料保存及傳遞，且由於序列化後資料格式為XML，為一個開放的標準，適合於現今的網路中。
• 但因XML格式完全開放自行定義，會導致不相容於所有應用程式的情況發生，而SOAP標準就成為應用程式之前XML資料格式的標準了，讓資料更具通透性。

XML Serialization實作

(1)建立一個類別包含Public的資料
(2)XML序列化和反序列化物件

• System.Xml.Serializtion
• 使用Stream物件
• 呼叫Serialize與Deserialize方法

Public Class MyBook
Public bookID As Integer
Public bookName As String
End Class
=====================
Imports System.IO
Imports System.Xml.Serialization
Public Class Form1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'1、建立及使用物件
Dim obj As New MyBook
obj.bookID = 10
obj.bookName = "琦真說童年"
'2、序列化XML物件
Dim ser As New XmlSerializer(GetType(MyBook))
Dim fs As New FileStream(Application.StartupPath & "\MyBook.xml", FileMode.Create)
ser.Serialize(fs, obj)
fs.Close()
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'3、反序列化還原物件
Dim ser As New XmlSerializer(GetType(MyBook))
Dim fs As New FileStream(Application.StartupPath & "\MyBook.xml", FileMode.Open)
Dim obj As MyBook = CType(ser.Deserialize(fs), MyBook)
fs.Close()
MessageBox.Show("Deseriablize OK...PublicBookName = " & obj.bookName)
End Sub
End Class
========================================
使用Attribute控制XML序列化
(1)建立一個類別包含Public資料
(2)XML序列化及反序列化物件
(3)如何使用Attribute控制XML序列化

• System.Xml.Serialization Namespace
• XmlRoot Attribute
• XmlElement Attribute
• XmlAttribute Attribute

(4)控制陣列型別的序列化

• XmlArray Attribute
• XmlArrayItem Attribute

=====================
Imports System.Xml.Serialization

Public Class MyProduct
Public productID As Integer
Public productName As String
End Class
=====================

Imports System.IO
Imports System.Xml.Serialization
Public Class Form1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'1、建立及使用物件

Dim obj As New MyProduct
obj.productID = 123
obj.productName = "可愛小寶具"


'2、序列化XML物件
Dim ser As New XmlSerializer(GetType(MyProduct))
Dim fs As New FileStream(Application.StartupPath & "\MyProduct.xml", FileMode.Create)
ser.Serialize(fs, obj)
fs.Close()
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'3、反序列化還原物件
Dim ser As New XmlSerializer(GetType(MyProduct))
dim fs as New FileStream(application.StartupPath & "\MyProduct.xml",FileMode.Open)
Dim obj As MyProduct = CType(ser.Deserialize(fs), MyProduct)
fs.Close()

MessageBox.Show("Deseriablize OK...PublicBookName = " & obj.productName)
End Sub
End Class
========================================
使用控制Array型別序列化
Imports System.Xml.Serialization

Public Class MyProduct
Public productID As Integer
Public productName As String
End Class
=====================

Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
'1、建立及使用物件
Dim obj As New Group
Dim emp1 As New Employee
Dim emp2 As New Employee
emp1.Name = "Jerry"
emp2.Name = "John"

obj.Employees(0) = emp1
obj.Employees(1) = emp2
'2、序列化XML物件
Dim ser As New XmlSerializer(GetType(Group))
Dim fs As New FileStream(Application.StartupPath & "\Group.xml", FileMode.Create)
ser.Serialize(fs, CType(obj, Group))
fs.Close()
End Sub

Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
'3、反序列化還原物件
Dim ser As New XmlSerializer(GetType(Group))
Dim fs As New FileStream(Application.StartupPath & "\Group.xml", FileMode.Open)

Dim obj As Group = CType(ser.Deserialize(fs), Group)
fs.Close()
MessageBox.Show("Deseriablize OK...Group = " & obj.Employees(0).Name)

End Sub