Making a Form stay on top of ALL other applications

Hi Guys

Thanks for the answers I was aware of "TopMost" but it didn't work quite as I expected. My project is that a window/form is created by the arrival of a file. The tag is flashed in the task bar to draw the users attention to it. If he does nothing then after a certain time then the form is made TopMost. It doesn't work. It only seems to work if the TopMost is set when the form is created not after a dely using a timer. I have done a work around by closing the original form and opening a new one with the TopMost set.

But doesn't answer my original question about the API SetWindowsPos. Why does it work in VB6 and not VB.Net. I thought an API was programming language independent as long as the parameters were passed OK it should work regardless.

Did you try

this.Topmost = true;


It makes the form appear topmost of all other forms.

Something in your code is not right. Here's what I just tried (using both SetWindowPos and TopMost)

I added a Timer to the form and set the Interval to 5000 (5 seconds). On form Load, I start the Timer, then I click a bunch of other programs to bring them on top of the form. After the 5 seconds, the form pops to the top and you can't bring another window in front of it. Here are the two methods:

<DllImport("user32.dll", SetLastError:=True)> _
Private Shared Function SetWindowPos(ByVal hWnd As IntPtr, ByVal hWndInsertAfter As IntPtr, _
                                     ByVal X As Integer, ByVal Y As Integer, ByVal cx As Integer, _
                                     ByVal cy As Integer, ByVal uFlags As UInt32) As Boolean
End Function

ReadOnly HWND_TOPMOST As New IntPtr(-1)
Shared ReadOnly SWP_NOSIZE As UInt32 = Convert.ToUInt32(&H1)
Shared ReadOnly SWP_NOMOVE As UInt32 = Convert.ToUInt32(&H2)

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
    'Either one of these does the trick
    SetWindowPos(Me.Handle, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOMOVE Or SWP_NOSIZE)
    'Me.TopMost = True
End Sub

So, either something is wrong with your code, or your system is a bit messed up.