Singleton 单件创建模式

'Singleton模式:一个类只会创建一个实例。
Module Module1

    Sub Main()
        Dim In1 As Singleton = Singleton.Intance
        In1.Name = "李小龙"
        Dim In2 As Singleton = Singleton.Intance

        System.Console.WriteLine(Object.ReferenceEquals(In1, In2) = True)
        System.Console.WriteLine(In1.Name)
        System.Console.WriteLine(In2.Name)
        System.Console.ReadLine()

    End Sub

End Module

Public Class Singleton

    Private Shared m_Intance As Singleton
    Private Shared m_Mutex As New System.Threading.Mutex '同步基元也可用于进程间同步
    Private m_Name As String
    Private Sub New()

    End Sub

    Public Shared Function Intance() As Singleton
        m_Mutex.WaitOne() '当在派生类中重写时，阻塞当前线程，直到当前的 System.Threading.WaitHandle 收到信号

        Try
            If m_Intance Is Nothing Then
                m_Intance = New Singleton   '释放 System.Threading.Mutex 一次
            End If
        Finally
            m_Mutex.ReleaseMutex()
        End Try
        Return m_Intance
    End Function

    Public Property Name() As String
        Get
            Return Me.m_Name
        End Get
        Set(ByVal value As String)
            Me.m_Name = value
        End Set
    End Property
End Class