VB中什么控件可以让其透明?

Option Explicit

Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hWnd As Long, ByVal nIndex As Long) As Long
Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hWnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long

Const LWA_COLORKEY = &H1
Const LWA_ALPHA = &H2
Const GWL_EXSTYLE = (-20)
Const WS_EX_LAYERED = &H80000
Const WS_EX_TRANSPARENT As Long = &H20&

Private Sub Form_Load()
Dim Ret As Long

Ret = GetWindowLong(Me.hWnd, GWL_EXSTYLE)
Ret = Ret Or WS_EX_LAYERED Or WS_EX_TRANSPARENT
SetWindowLong Me.hWnd, GWL_EXSTYLE, Ret
SetLayeredWindowAttributes Me.hWnd, 0, 200, LWA_ALPHA '第三个参