VB .NET Dual Monitor

2006-10-07

Question

_{Saturday, October 7, 2006 7:34 AM}

Hi,

I'm experimenting with dual monitors and VB .net 2003. (I'm pretty new to the language... sorry if the question is lame)

I've been tinkering with System.Windows.Forms.Screen.AllScreens and can get screen information (device names, bounds, working area, etc..)

Can anyone offer a simple example of opening a form on a secondary monitor from the primary screen?
If i can get this then I should be fine with what I am trying to accomplish.

Any help is appreciated.

Thanks!

All replies (12)

_{Saturday, October 7, 2006 8:12 AM ✅Answered | 7 votes}

All you need to do to show a form on a specifi screen is to set its Location property so it is in the specified screen Bounds:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim form As New Form

Dim screen As Screen

' We want to display a form on screen 1

screen = screen.AllScreens(1)

' Set the StartPosition to Manual otherwise the system will assign an automatic start position

form.StartPosition = FormStartPosition.Manual

' Set the form location so it appears at Location (100, 100) on the screen 1

form.Location = screen.Bounds.Location + new Point(100, 100)

' Show the form

form.ShowDialog(Me)

End Sub

_{Saturday, October 7, 2006 8:10 AM}

Hi,

You can use the WorkingArea property of the Screen object. Here's an example (not tested):

Dim myScreens() As Screen = Screen.AllScreens
If (myScreens.Length = 2) Then

'Position form 1 in the middle of screen 1
Me.Left = myScreens(0).WorkingArea.Width / 2 - Me.Width / 2
Me.Top = myScreens(0).WorkingArea.Height / 2 - Me.Height / 2

'Position the top left corner of form 2 in the middle of screen 2
Dim myForm2 As New Form2
myForm2.Show()
myForm2.Left = myScreens(0).Bounds.Width + myScreens(1).WorkingArea.Width / 2
myForm2.Top = myScreens(1).WorkingArea.Height / 2
End If

Hope this helps,

_{Tuesday, October 10, 2006 11:07 AM}

Thanks for the help here.

It's exactly what i was after.

_{Tuesday, October 10, 2006 11:27 AM}

FYI, please note that the bounds property of the screen object is the entire screen, while the workingarea is the desktop area of the display, excluding taskbars, docked windows, and docked tool bars.

Placing a form within the bounds of a screen, might hide portions of it behind a taskbar or docked window.

Regards,

_{Tuesday, January 8, 2008 6:34 AM}

Hi,

Is it possible to get monitor information of some other machine? In particular, I want to know how many monitors are connected to some other machine.

_{Friday, January 25, 2008 4:21 PM}

hello all i seem to be having an issue querying attached display devices ...

i have a GeForce 7900GT 256MB 256-bit GDDR3 PCI Express x16 and a 42" Panasonic 720p HD TV

only my monitor ( 22" Gateway Flat Panel ) shows up in Screen.AllScreens

I'm connected to my gateway monitor via the dvi1 port on the video card, then a dvi - vga connector that goes into a kvm switch to share the monitor between 2 computers.

The TV is connected to the dvi2 port on the video card and a dvi-hdmi cable is used to connect it to the tv.

I can see the TV in the display properties and set it up to clone the screen or make it horiz / vert spread etc,

but when I'm in my app, I can't seem to get it to show up in the AllScreens collection.

As I'm writing, I'm going to try and set up the tv as the primary display and see if it finds it in the collection then.

Also I'll try without the KVM switch. (Funny what you think of when youo're not around to try it)

Until I get home tonight to try any ideas?

_{Monday, January 28, 2008 7:36 AM}

well to much dismay i was unable to successfully connect both displays how i wanted ... my flat screen has the resolution of 1680*1050 while my tv's a 1280*120 hdtv ... when both resoltions are configured my flat screen becomes pink and distorted @ 720 instead of keeping its 1680*1050 resolution. I don't think a stretch is possible like that but i wanted to do a clone or something. I want to display two different things on two different displays.

_{Thursday, February 7, 2008 12:59 AM}

Hi Mark,

Connection problems are a little bit off-topic here.

Still, from my experience on other formus, Panasonic TVs seem to have some issues when connected to PC.

Of course, I know you got the latest drivers for your graphic card and the cables are OK. (EDID data flows from one end to another so you can actually see the name of the monitor and TV on PC)

If you have enough info about your hardware, you may try PowerStrip which will alow you to manually configure all the frequences and timings.

Good luck!

And now, my question:

System.Windows.Forms.Screen.AllScreens enumeration seem to contain a virtual display also.

How can I avoid it?

I've tested this on two different computers (VB.Net 2005, XP Professional SP2, .Net Framework 2.0):

The first - PC with XP Profi SP2, ATI graphics card, two monitors (HERCULES PROPHETVIEW on VGA, default monitor, and SAMSUNG LE40M86 on DVI - secondary monitor)

The second - DELL laptop with XP Profi SP2, (default monitor, Intel 915 graphics chip)

In first case, the enumeration contains 3 monitors DISPLAY1, DISPLAY2 and DISPLAYV2:

(0) {Bounds = {Primary = True DeviceName = "\.\DISPLAY1} (bounds = 1280x1024 working area = 1280x994)

(1) {Bounds = {Primary = False DeviceName = "\.\DISPLAY2} (bounds = -1920x1080 w.a. = -1920x1080)

(2) {Bounds = {Primary = False DeviceName = "\.\DISPLAYV2} (bounds = 1280x1024 w.a. = 1280x1024)

Here, "DisplayV2" is in fact Display1 BUT its working area doesn't exclude the taskbar(!!!)

In the second case, primary DISPLAY1 is also accompanied by a secondary "DISPLAYV1", also ignoring the taskbar...

Any clues where do these virtual display came from?

Thanks.

Mircea.

_{Thursday, July 3, 2008 12:19 PM}

hi,

try this

form.StartPosition := dotNET.System_Windows_Forms.FormStartPosition.CenterScreen;

Attitude

_{Tuesday, October 28, 2008 4:12 PM}

Mark-New Hudson Technologies,LLC said: