在对象中引发的事件也会在同一类的另一个对象中触发

Question

VB . NET 2010, Framework 3.5

试着理解为什么会这样。我从同一个Class1创建了两个对象。GlobalClass1具有全局作用域，LocalClass1具有模块作用域。

在UControl的Load事件中，我设置了LocalClass1 = GlobalClass1从这一点上，任何时候我改变GlobalClass1.TestProperty的值，属性值也在LocalClass1中更新。当GlobalClass1事件触发时，LocalClass1中的Events被触发。

这是我正在寻找的结果=>能够在其他几个类模块和用户控件中有一个全局对象的事件。

我不太明白为什么简单地设置本地对象=全局对象导致本地对象自动更新它的属性值时，全局对象的属性更新或为什么本地事件自动触发时，全局对象引发的事件?

Module Module1
    Public WithEvents frm As New MainForm
    Public WithEvents GlobalClass1 As New Class1
    Public Sub Main()
        frm.Init()
       frm.ShowDialog()
   End Sub
End Module

---

Public Class MainForm
    Private uiUserControl As UControl
    Public Function Init() As Boolean
        uiUserControl = New UControl
        uiUserControl.Location = New System.Drawing.Point(60, 80)
        Me.Controls.Add(uiUserControl)
        Return True
    End Function
    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        Static count As Integer
        GlobalClass1.TestProperty = count.ToString ' This line propagates to the Private Local LocalClass1 and cause it's event to fire??
        count += 1
    End Sub
End Class

---

Public Class UControl
    Private WithEvents LocalClass1 As New Class1
    Private Sub UControl_Load(sender As Object, e As System.EventArgs) Handles Me.Load
        LocalClass1 = GlobalClass1
    End Sub
    Private Sub LocalClass1_TestPropertyChanged() Handles LocalClass1.TestEvent
        Me.TextBox1.Text = LocalClass1.TestProperty  'This Event fires when events are raised in the other object => GlobalClass1??
    End Sub
End Class

---

Public Class Class1
    Public Event TestEvent()
    Private _testProperty As String
    Public Property TestProperty() As String
        Get
            Return _testProperty
        End Get
        Set(ByVal value As String)
            _testProperty = value
            RaiseEvent TestEvent()
        End Set
    End Property
End Class

---

Answer 1

类实例(对象)都引用堆上分配给它们的相同内存空间。

Answer 2

from comments:

问题出在这一行:LocalClass1 = GlobalClass1

它们一开始是不同的对象，但后来你让它们指代同一事物。对象引用(或引用类型)与值类型(如integer)的工作方式不同:

Dim x As Int32
Dim y As Int32 = 42
x = y

作为值类型，y的值被赋给x。引用类型本质上是指针的包装器或别名。因此，您的赋值代码将指向New Class1的原始指针替换为已赋值给GlobalClass1的指针

在MSDN阅读更多关于值与引用类型的信息