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Imports System.Deployment.Application
Imports System.Runtime.InteropServices
Imports System.Reflection
Imports System.Threading
Friend Class Main
Inherits System.Windows.Forms.Form
Protected Overrides Sub WndProc(ByRef Message As Message)
If Message.Msg = SingleInstance.WM_SHOWFIRSTINSTANCE Then
ShowWindow()
Else
'MessageBox.Show("Application already run !")
End If
MyBase.WndProc(Message)
End Sub
Private Sub ShowWindow()
Me.WindowState = FormWindowState.Normal
Me.Focus()
End Sub
Private Sub cmdUpdate_Click(Sender As Object, e As EventArgs) Handles cmdUpdate.Click
If ApplicationDeployment.IsNetworkDeployed Then
If ApplicationDeployment.CurrentDeployment.CheckForUp date(False) Then
ApplicationDeployment.CurrentDeployment.Update()
MsgBox("The application has been updated and will now restart.", MsgBoxStyle.Information)
My.Settings.IsRestarting = True
My.Settings.Save()
Application.Restart()
End If
End If
End Sub
Friend WithEvents cmdUpdate As System.Windows.Forms.Button
Private Sub InitializeComponent()
Me.cmdUpdate = New System.Windows.Forms.Button()
Me.SuspendLayout()
'
'cmdUpdate
'
Me.cmdUpdate.Location = New System.Drawing.Point(132, 175)
Me.cmdUpdate.Name = "cmdUpdate"
Me.cmdUpdate.Size = New System.Drawing.Size(75, 23)
Me.cmdUpdate.TabIndex = 0
Me.cmdUpdate.Text = "Button1"
Me.cmdUpdate.UseVisualStyleBackColor = True
'
'Main
'
Me.ClientSize = New System.Drawing.Size(284, 262)
Me.Controls.Add(Me.cmdUpdate)
Me.Name = "Main"
Me.ResumeLayout(False)
End Sub
End Class
Namespace My
' The following events are availble for MyApplication:
'
' Startup: Raised when the application starts, before the startup form is created.
' Shutdown: Raised after all application forms are closed. This event is not raised if the application terminates abnormally.
' UnhandledException: Raised if the application encounters an unhandled exception.
' StartupNextInstance: Raised when launching a single-instance application and the application is already active.
' NetworkAvailabilityChanged: Raised when the network connection is connected or disconnected.
Partial Friend Class MyApplication
Private Sub MyApplication_Startup(sender As Object, e As ApplicationServices.StartupEventArgs) Handles Me.Startup
If My.Settings.IsRestarting Then
My.Settings.IsRestarting = False
My.Settings.Save()
Thread.Sleep(3000)
End If
If Not SingleInstance.Start() Then
SingleInstance.ShowFirstInstance()
e.Cancel = True
End If
End Sub
Private Sub MyApplication_Shutdown(sender As Object, e As EventArgs) Handles Me.Shutdown
SingleInstance.Stop()
End Sub
End Class
End Namespace
Public NotInheritable Class SingleInstance
Public Shared ReadOnly WM_SHOWFIRSTINSTANCE As Integer = WinApi.RegisterWindowMessage("WM_SHOWFIRSTINSTANCE|{0}", ProgramInfo.AssemblyGuid)
Private Shared Mutex As Mutex
Public Shared Function Start() As Boolean
Dim lIsOnlyInstance As Boolean
Dim sMutexName As String
lIsOnlyInstance = False
sMutexName = String.Format("Local\{0}", ProgramInfo.AssemblyGuid)
' If you want your app to be limited to a single instance
' across ALL SESSIONS (multiple users & terminal services),
' then use the following line instead:
' sMutexName = String.Format("Global\\{0}", ProgramInfo.AssemblyGuid);
Mutex = New Mutex(True, sMutexName, lIsOnlyInstance)
Return lIsOnlyInstance
End Function
Public Shared Sub ShowFirstInstance()
WinApi.PostMessage(New IntPtr(WinApi.HWND_BROADCAST), WM_SHOWFIRSTINSTANCE, IntPtr.Zero, IntPtr.Zero)
End Sub
Public Shared Sub [Stop]()
Mutex.Close()
End Sub
End Class
Public NotInheritable Class WinApi
<DllImport("user32")> _
Public Shared Function RegisterWindowMessage(message As String) As Integer
End Function
<DllImport("user32")> _
Public Shared Function PostMessage(hwnd As IntPtr, msg As Integer, wparam As IntPtr, lparam As IntPtr) As Boolean
End Function
<DllImport("user32")> _
Public Shared Function ShowWindow(hWnd As IntPtr, nCmdShow As Integer) As Boolean
End Function
<DllImport("user32")> _
Public Shared Function SetForegroundWindow(hWnd As IntPtr) As Boolean
End Function
Public Shared Function RegisterWindowMessage(Template As String, ParamArray Values As Object()) As Integer
Return RegisterWindowMessage(String.Format(Template, Values))
End Function
Public Shared Sub ShowToFront(Window As IntPtr)
ShowWindow(Window, SW_SHOWNORMAL)
SetForegroundWindow(Window)
End Sub
Public Const HWND_BROADCAST As Integer = &HFFFF
Public Const SW_SHOWNORMAL As Integer = 1
End Class
Public NotInheritable Class ProgramInfo
Public Shared ReadOnly Property AssemblyGuid As String
Get
Dim aAttributes As Object()
aAttributes = Assembly.GetEntryAssembly.GetCustomAttributes(GetT ype(GuidAttribute), False)
If aAttributes.Length = 0 Then
AssemblyGuid = String.Empty
Else
AssemblyGuid = DirectCast(aAttributes(0), GuidAttribute).Value
End If
End Get
End Property
End Class
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