VB.Net Tutorial/GUI Applications/Application Thread

Application Thread

<source lang="vbnet">Imports System.Windows.Forms Public Class Form1

   Inherits System.Windows.Forms.Form
   Public Sub New()
       MyBase.New()
       InitializeComponent()
   End Sub
   Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
       If disposing Then
           If Not (components Is Nothing) Then
               components.Dispose()
           End If
       End If
       MyBase.Dispose(disposing)
   End Sub
   Private components As System.ruponentModel.IContainer
   Friend WithEvents button4 As System.Windows.Forms.Button
   Friend WithEvents button3 As System.Windows.Forms.Button
   Friend WithEvents button2 As System.Windows.Forms.Button
   Friend WithEvents button1 As System.Windows.Forms.Button
   <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
       Me.button4 = New System.Windows.Forms.Button()
       Me.button3 = New System.Windows.Forms.Button()
       Me.button2 = New System.Windows.Forms.Button()
       Me.button1 = New System.Windows.Forms.Button()
       Me.SuspendLayout()
       "
       Me.button4.Location = New System.Drawing.Point(24, 127)
       Me.button4.Name = "button4"
       Me.button4.Size = New System.Drawing.Size(144, 23)
       Me.button4.TabIndex = 7
       Me.button4.Text = "Show MessageBox"
       "
       Me.button3.Location = New System.Drawing.Point(24, 90)
       Me.button3.Name = "button3"
       Me.button3.Size = New System.Drawing.Size(144, 23)
       Me.button3.TabIndex = 6
       Me.button3.Text = "Throw Exception"
       "
       Me.button2.Location = New System.Drawing.Point(24, 53)
       Me.button2.Name = "button2"
       Me.button2.Size = New System.Drawing.Size(144, 23)
       Me.button2.TabIndex = 5
       Me.button2.Text = "Application.ExitThread"
       "
       "button1
       "
       Me.button1.Location = New System.Drawing.Point(24, 16)
       Me.button1.Name = "button1"
       Me.button1.Size = New System.Drawing.Size(144, 23)
       Me.button1.TabIndex = 4
       Me.button1.Text = "Application.Exit"
       "
       "Form1
       "
       Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
       Me.ClientSize = New System.Drawing.Size(192, 166)
       Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.button4, Me.button3, Me.button2, Me.button1})
       Me.Name = "Form1"
       Me.Text = "Applications"
       Me.ResumeLayout(False)
   End Sub
   Shared Sub App_Exit(ByVal sender As Object, ByVal e As EventArgs)
       System.Diagnostics.Debug.WriteLine("App_Exit")
   End Sub
   Shared Sub App_Idle(ByVal sender As Object, ByVal e As EventArgs)
       System.Diagnostics.Debug.WriteLine("App_Idle")
   End Sub
   Shared Sub App_ThreadingException(ByVal sender As Object, ByVal e As System.Threading.ThreadExceptionEventArgs)
       System.Diagnostics.Debug.WriteLine("App_ThreadException")
       Dim msg As String = "A problem has occurred in this application." & vbCrLf & vbCrLf & _
           vbTab & e.Exception.Message & vbCrLf & vbCrLf & _
           "Would you like to continue the application so that " & vbCrLf & _
           "you can save your work?"
       Dim res As DialogResult = MessageBox.Show(msg, "Unexpected Error", MessageBoxButtons.YesNo)
       If res = System.Windows.Forms.DialogResult.Yes Then Exit Sub
       Application.Exit()
   End Sub
   Shared Sub DumpThreadID(ByVal name As String)
       System.Diagnostics.Debug.WriteLine(name & " thread id= " & System.AppDomain.GetCurrentThreadId().ToString())
   End Sub
   Shared Sub DummyThreadStart()
       DumpThreadID("Dummy Thread")
       AddHandler Application.ThreadExit, New EventHandler(AddressOf App_ThreadExit)
   End Sub
   Shared Sub Main()
       AddHandler Application.ThreadException, New System.Threading.ThreadExceptionEventHandler(AddressOf App_ThreadingException)
       AddHandler Application.Idle, New EventHandler(AddressOf App_Idle)
       AddHandler Application.ThreadExit, New EventHandler(AddressOf App_ThreadExit)
       AddHandler Application.ApplicationExit, New EventHandler(AddressOf App_Exit)
       DumpThreadID("UI Thread")
       Dim dummythread As System.Threading.Thread = New System.Threading.Thread(New System.Threading.ThreadStart(AddressOf DummyThreadStart))
       dummythread.Start()
       Application.Run(New Form1())
   End Sub
   Shared Sub App_ThreadExit(ByVal sender As Object, ByVal e As EventArgs)
       System.Diagnostics.Debug.WriteLine("App_ThreadExit on thread id= " & System.AppDomain.GetCurrentThreadId().ToString())
   End Sub
   Private Sub button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button1.Click
       Application.Exit()
   End Sub
   Private Sub button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button2.Click
       Application.ExitThread()
   End Sub
   Private Sub button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button3.Click
       Throw New System.IO.FileLoadException()
   End Sub

End Class</source>