I just stat to study visual basic .net
I would like to ask about how to continue application.
For example
Private Sub UI_BT_SAVE_STOP_Click(sender As Object, e As EventArgs) Handles UI_BT_STOP.Click
Stop
End Sub
then , application will stop on the middle of processing(like a stop button on the visual studio)
I was trying to make continue button, but I can not find continue function to change my application status from stop to continue.
is there anyway to continue application again ?
thanks
There's nothing quite like that but you could always try importing the sleep function, seen here:
https://stackoverflow.com/a/469358/1504882
This will suspend everything the application is doing though.
Related
I'd like to know if there is a possible way to handle a closing application in Visual Studio 2008 without using the dispose event handler.
If my application crashes or if I close it while it is running:
Private Sub Foo_Disposed(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Disposed
Is not called.
This result in a serious problem, because I'm currently working on multiple Excel files and they remain open after the application crashes or I close it while it's running.
Is there a way to handle this kind of closing application event?
In a normal situation when your application is simply closing you can subscribe to the MyApplication.Shutdown event and close your excel documents in there.
Subscribing to the event can be done through these steps:
Right-click your project in the Solution Explorer and press Properties.
Go to the Application pane and press View Application Events.
In the file that was opened, either write the event handler on your own or let VS do it by first selecting (MyApplication Events) in the left combo box above the text editor, then selecting Shutdown in the right combo box.
Now you should have an event handler that looks something like the one below. Just go ahead and do your cleanup in there:
Private Sub MyApplication_Shutdown(sender As Object, e As System.EventArgs) Handles Me.Shutdown
'Do your cleanup here...
End Sub
For application crashes caused by CLR exceptions you can use the AppDomain.UnhandledException event, but for more serious crashes there isn't very much you can do.
A workaround would be to create another application which monitors your main app. When the other app senses that your main application's process has been terminated, it will close the excel documents. The tricky part with this solution is passing the information necessary for the other app to close the documents.
The problem is happening on 2 of the company's computers and on a client computer, but we can not identify a pattern.
I was able to reproduce the error using a simple program that only opens an OpenFileDialog. The program must be run by the generated executable itself (NOT by Debug) and it is still running in the background even after closing. Below is the code of the program, along with a link to download the project and a video demonstrating the error.
Code:
Public Class Form1
Private ofdAbrir As Windows.Forms.OpenFileDialog
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
ofdAbrir = New Windows.Forms.OpenFileDialog
ofdAbrir.ShowDialog()
ofdAbrir.Dispose()
ofdAbrir = Nothing
End Sub
End Class
As you can see in the code above, I only have one form, so it is not the case that some form remains open and it is also not related to threads running since none is created.
To reproduce the problem, click on Button1, cancel the OpenFileDialog and try to close the form (clicking on X). The form apparently will close, but you will see at task manager that it still running. The big mystery is that this problem does not happens in all computers.
Video: https://drive.google.com/open?id=1sfdVUGQlwYNCQkl1Ht-cJSOb4433sqnT
Project: https://drive.google.com/open?id=1d4oJYUjaaZ9xnRj4CX3HXOQPqwMZmE0V
I couldn't reproduce the problem, but how about using this method:
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
Using ofdAbrir As New Windows.Forms.OpenFileDialog
ofdAbrir.ShowDialog()
MsgBox(ofdAbrir.FileName)
End Using
End Sub
I've seen the video u posted...It is not your application that is running rather it is the vsHost.exe that is running :)...The problem shouldn't occur if u run the app outside visual studio.
If the problem is still there,just disable Enable Diagnostic Tools while debugging from Tools > Options > Debugging > Uncheck Enable Diagnostic Tools while debugging
Also u can disable Visual Studio hosting service from Project > Project Properties > Uncheck Enable the Visual Studio hosting service
I'm currently working with the iTunes COM with .NET, and something I came across previously, which stopped me using it, has happened again and I can't for the life of me figure it out.
When I go to close iTunes during or after my program has closed, it tells me something is still using the "Application Scripting Interface", COM is still connected.
This is what I have (removed what is not required)
Private Sub frmMain_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
AddHandler itunes.OnAboutToPromptUserToQuitEvent, AddressOf itunes_OnAboutToPromptUserToQuitEvent
End Sub
Private Sub itunes_OnAboutToPromptUserToQuitEvent()
System.Runtime.InteropServices.Marshal.ReleaseComObject(itunes)
End Sub
So, the above code does disconnect the COM to the extent that I need to restart iTunes to use it again, but, it doesn't get rid of the Application Scripting error. Meaning, I still need to click quit after the error dialog comes up. Everything else works fine, apart from this.
Any idea?
-- I've had a look at other questions that had this issue, but none of them resolved it for me. I'm not sure if the event doesn't work anymore with this current version of iTunes, but, it doesn't seem to work currently either way.
Had same issue with COM and Office, this solved it;
While System.Runtime.InteropServices.Marshal.ReleaseComObject(itunes) <> 0
Application.DoEvents()
End While
I have a VB.Net 2012 app (running directly, not in the IDE) for receiving scanned data that stays on top and retains focus. Here is the code used to accomplish this:
Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
Me.TopMost = True
Me.TopMost = False
Me.Activate()
txtScanItem.Focus()
End Sub
works perfectly, but, it only functions correctly if the IDE is running and has a project loaded, any project, and simply sitting idle (not running)
how does an IDE sitting idle cause the code to function properly? perhaps some sequence of events at the OS level caused by the IDE when loading a project? note that if the IDE is up but not loaded with a project the code fails to function correctly
Visual Studio Express 2012
Windows 7 Professional
thanks
may be a long shot, but have you build the app in "Release" instead of "Debug"?
Debug Visual Studio Release in .NET
VB.NET program.
While developing on Visual Studio Express 2010, there are two buttons: Start Debugging, and Stop Debugging.
Well, while debugging, I close my application (the red X button). However, when I look back at Visual Studio, it seems to still be in debugging mode (the Start button is disabled, and the Stop button is enabled). So I have to manually press the Stop button.
I remember it was not like this before.
Perhaps it is because my application uses multiple forms or something? Then I am probably missing something rather important... Any ideas?
You've got something open somewhere. You can force the entire app to quit by adding
End
in the form's FormClosed event:
Private Sub Form1_FormClosed(sender As Object, e As System.Windows.Forms.FormClosedEventArgs) Handles Me.FormClosed
End
End Sub
Are you doing any threading? Shutting down your primary app leaving threads running will cause what you are seeing. Also app design can cause what you are seeing. You can start your vb.net app running a "main" procedure, but if you don't provide an exit for it, the app will continue to run.
Ensure that all hidden forms (if any) are closed, properly dispose all objects.
If you are hiding any form and forgot to close it in your application this scenario may happen. Or if you are using threading in your application and they are not terminating properly then also it happens.