Rod (or someone), when the VB.net code stops at a breakpoint, the user window disappears and the debug window displays. What is the short-cut key to view the user window without resuming code execution?

Am at p. 156, and example program ChangeFormFont motivated this question.

I'm not sure I understand. By "user window" do you mean the form that the program displays to the user?

Unfortunately a VB program can't update the form while it is paused in the debugger because it cannot execute to process Window events. You can use the Task Manager or Alt-Tab to switch to that window but you'll only see a blank area.

Of am I missing the question entirely?

__________________
Rod

Rod Stephens, Microsoft MVP

Essential Algorithms: A Practical Approach to Computer Algorithms

(Please post reviews at Amazon or wherever you shop!)

Yes, thank you, Rod. You have understood the question.

When the VB code "breaks", I need to see what the end-user sees on the application's screen. It seems that VS2010 does not support this.

Here is my workaround. Every second a Timer routine calls this routine to copy the screen to the clipboard, and then save it to disk:
Public Sub clip()
SendKeys.Send("{PRTSC}")
Dim grabpicture As System.Drawing.Image
grabpicture = My.Computer.Clipboard.GetImage()
grabpicture.Save("c:\clipboard.bmp")
End Sub

Then, after the "break", type this in the Immediate window to display the screen:
Process.Start("C:\clipboard.bmp")

Instead of the Timer routine, do you think it would be possible to write a VS2010 add-in which intercepted the breakpoint interrupt and ran the clip() subroutine before leaving the user's screen? It would then hand back to the usual break-point routine.

BTW, have now reached p. 265 (but am skipping WPF this time around).

That's a pretty clever workaround. I may have to steal it for an example ;-)

I don't know if you can do that (reasonably) in an add-in. I haven't done much with Visual Studio add-ins but there's a DebuggerEvents object that raises an OnEnterBreakMode event when you enter break mode. Unfortunately it seems to wait until the form is no longer visible so if I try to grab an image then I get an image of the IDE.

I've attached my test add-in project.

Let me know if you find a solution.

Attached Files

GetFormImageOnBreak.zip (14.5 KB, 6 views)

__________________
Rod

Rod Stephens, Microsoft MVP

Essential Algorithms: A Practical Approach to Computer Algorithms

(Please post reviews at Amazon or wherever you shop!)

Another approach would be to make a macro to grab the form. Then set the breakpoint's When Hit action to run the macro.

Unfortunately I can't seem to get the macro to copy an image to the clipboard. For some reason the clipboard always stays empty.

__________________
Rod

Rod Stephens, Microsoft MVP

Essential Algorithms: A Practical Approach to Computer Algorithms

(Please post reviews at Amazon or wherever you shop!)

Thank you for investigating this, Rod. No doubt someone will discover the "obvious" answer