程序代码：

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load   
    With Me.TrackBar1   
        .TickStyle = TickStyle.None   
        .Maximum = 100   
        .Minimum = 0   
        .Value = 100   
    End With  
    Me.Text = String.Format("不透明度 - {0}%", TrackBar1.Value)   
End Sub  
  
  
Private Sub TrackBar1_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles TrackBar1.ValueChanged   
    Me.Opacity = TrackBar1.Value / 100   
    Me.Text = String.Format("不透明度 - {0}%", TrackBar1.Value)   
End Sub 
    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        With Me.TrackBar1
            .TickStyle = TickStyle.None
            .Maximum = 100
            .Minimum = 0
            .Value = 100
        End With
        Me.Text = String.Format("不透明度 - {0}%", TrackBar1.Value)
    End Sub


    Private Sub TrackBar1_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles_
TrackBar1.ValueChanged
        Me.Opacity = TrackBar1.Value / 100
        Me.Text = String.Format("不透明度 - {0}%", TrackBar1.Value)
    End Sub