Private Sub CheckBox1_CheckedChanged(sender as Object, e as EventArgs) _ 
     Handles CheckBox1.CheckedChanged

   MessageBox.Show("You are in the CheckBox.CheckedChanged event.")

End Sub

' 导入命名空间
Imports System.Windows.Forms
Imports System.Drawing
Imports System.Drawing.Drawing2D

public class CheckBoxEvent
   public Shared Sub Main
        Application.Run(New FrmCheckBox)
   End Sub
End class


Public Class FrmCheckBox
   Inherits System.Windows.Forms.Form

#Region " Windows Form Designer generated code "

   Public Sub New()
      MyBase.New()

      'This call is required by the Windows Form Designer.
      InitializeComponent()

      'Add any initialization after the InitializeComponent() call

   End Sub

   'Form overrides dispose to clean up the component list.
   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
   Friend WithEvents chkItalic As System.Windows.Forms.CheckBox
   Friend WithEvents lblOutput As System.Windows.Forms.Label
   Friend WithEvents chkBold As System.Windows.Forms.CheckBox

   'Required by the Windows Form Designer
   Private components As System.ComponentModel.Container

   'NOTE: The following procedure is required by the Windows Form Designer
   'It can be modified using the Windows Form Designer.  
   'Do not modify it using the code editor.
   <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
      Me.lblOutput = New System.Windows.Forms.Label()
      Me.chkItalic = New System.Windows.Forms.CheckBox()
      Me.chkBold = New System.Windows.Forms.CheckBox()
      Me.SuspendLayout()
      '
      'lblOutput
      '
      Me.lblOutput.Font = New System.Drawing.Font("Microsoft Sans Serif", 11.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.lblOutput.Location = New System.Drawing.Point(48, 24)
      Me.lblOutput.Name = "lblOutput"
      Me.lblOutput.Size = New System.Drawing.Size(208, 24)
      Me.lblOutput.TabIndex = 0
      Me.lblOutput.Text = "Watch the font style change"
      '
      'chkItalic
      '
      Me.chkItalic.Font = New System.Drawing.Font("Microsoft Sans Serif", 9.75!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.chkItalic.Location = New System.Drawing.Point(152, 64)
      Me.chkItalic.Name = "chkItalic"
      Me.chkItalic.Size = New System.Drawing.Size(64, 24)
      Me.chkItalic.TabIndex = 2
      Me.chkItalic.Text = "Italic"
      '
      'chkBold
      '
      Me.chkBold.Font = New System.Drawing.Font("Microsoft Sans Serif", 9.75!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.chkBold.Location = New System.Drawing.Point(80, 64)
      Me.chkBold.Name = "chkBold"
      Me.chkBold.Size = New System.Drawing.Size(56, 24)
      Me.chkBold.TabIndex = 1
      Me.chkBold.Text = "Bold"
      '
      'FrmCheckBox
      '
      Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
      Me.ClientSize = New System.Drawing.Size(292, 117)
      Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.chkItalic, Me.chkBold, Me.lblOutput})
      Me.Font = New System.Drawing.Font("Microsoft Sans Serif", 9!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.Name = "FrmCheckBox"
      Me.Text = "CheckBoxTest"
      Me.ResumeLayout(False)

   End Sub

#End Region

   Private Sub chkItalic_CheckedChanged _
      (ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles chkItalic.CheckedChanged

      lblOutput.Font = New Font("Microsoft Sans Serif", _
         lblOutput.Font.Size, lblOutput.Font.Style Xor FontStyle.Italic)
   End Sub 

   Private Sub chkBold_CheckedChanged _
      (ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles chkBold.CheckedChanged

      lblOutput.Font = New Font("Microsoft Sans Serif", _
         lblOutput.Font.Size, lblOutput.Font.Style Xor FontStyle.Bold)
   End Sub 

End Class