Source code berikut untuk Memanipulasi ShowIn Taskbar pada Form.

Buat 1 project dengan :
1 Form
1 CheckBox

Copy source code berikut pada Form :

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 Const GWL_EXSTYLE = (-20)
Private Const WS_EX_APPWINDOW = &H40000

Private Function ShowInTheTaskbar(frm As Form, b As Boolean)
Dim l As Long
frm.Hide
l = IIf(b, Not WS_EX_APPWINDOW, WS_EX_APPWINDOW)
SetWindowLong frm.hWnd, GWL_EXSTYLE, (GetWindowLong(hWnd, GWL_EXSTYLE) And l)
frm.Show
End Function

Private Sub Check1_Click()
ShowInTheTaskbar Me, Check1.Value = 1
End Sub

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