Private Sub CreateMyOpaqueForm()
   ' Create a new form.
   Dim form2 As New Form()
   ' Set the text displayed in the caption.
   form2.Text = "My Form"
   ' Set the opacity to 75%.
   form2.Opacity = 0.75
   ' Size the form to be 300 pixels in height and width.
   form2.Size = New Size(300, 300)
   ' Display the form in the center of the screen.
   form2.StartPosition = FormStartPosition.CenterScreen

   ' Display the form as a modal dialog box.
   form2.ShowDialog()
End Sub

' 导入命名空间
Imports System.Windows.Forms

public class FormFadeOut
   public Shared Sub Main
        Application.Run(New Form1)
   End Sub
End class

Public Class Form1
    Private Sub ActClose_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ActClose.Click
        Dim counter As Integer

        For counter = 90 To 10 Step -5
            Me.Opacity = counter / 100
            Me.Refresh()
            Threading.Thread.Sleep(100)
        Next counter
        Me.Close()
    End Sub
End Class


<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
Partial Class Form1
    Inherits System.Windows.Forms.Form

    'Form overrides dispose to clean up the component list.
    <System.Diagnostics.DebuggerNonUserCode()> _
    Protected Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing AndAlso components IsNot Nothing Then
            components.Dispose()
        End If
        MyBase.Dispose(disposing)
    End Sub

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

    '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.ActClose = New System.Windows.Forms.Button
        Me.SuspendLayout()
        '
        'ActClose
        '
        Me.ActClose.Location = New System.Drawing.Point(104, 112)
        Me.ActClose.Name = "ActClose"
        Me.ActClose.Size = New System.Drawing.Size(75, 23)
        Me.ActClose.TabIndex = 0
        Me.ActClose.Text = "Close"
        Me.ActClose.UseVisualStyleBackColor = True
        '
        'Form1
        '
        Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
        Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
        Me.ClientSize = New System.Drawing.Size(292, 266)
        Me.Controls.Add(Me.ActClose)
        Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
        Me.MaximizeBox = False
        Me.Name = "Form1"
        Me.Text = "Fading Form"
        Me.ResumeLayout(False)

    End Sub
    Friend WithEvents ActClose As System.Windows.Forms.Button

End Class