How to Open console in VB - vb.net

I currently have a console application by using the setting illustrated in the image bellow. However Now I wish to open multiple forms with the console so I'm wondering if I can somehow open multiple forms or open the console within a Windows Forms Application

#tinstaafl can you share this extra programming or a link to a
solution. Thanks
Here's a couple of links:
Console and WinForm together for easy debugging
Console Enhancements
Here's a conversion of the first one. You'll need a form with a checkbox name "CheckBox1":
Imports System.Runtime.InteropServices
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
End Sub
Private Sub CheckBox1_CheckedChanged(sender As Object, e As EventArgs) Handles CheckBox1.CheckedChanged
If CheckBox1.Checked Then
Win32.AllocConsole()
Console.WriteLine("Done!")
Else
Win32.FreeConsole()
End If
End Sub
End Class
Public Class Win32
<DllImport("kernel32.dll")> Public Shared Function AllocConsole() As Boolean
End Function
<DllImport("kernel32.dll")> Public Shared Function FreeConsole() As Boolean
End Function
End Class
Everytime you click the checkbox you show or hide the console. You can write to and read from the same as any console app.

Forms and Console applications are very different. So much so that generally speaking a process either needs to be a form or console application. Forms applications are implemented with a message pump and console applications are command line drive. It is possible to a degree to run a form within a console, and vice versa, but generally not recommended. If you truly need both I would highly encourage you to use 2 processes.
If you could elaborate a bit more on your use case we may be better able to help you out.

So this is very cool. In the designer just add a checkbox using the Toolbox common controls.
Then double click on the new "CheckBox1" and that will automatically insert this sub routine:
Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged
End Sub
Then all you have to do is add this code:
If CheckBox1.Checked Then
Win32.AllocConsole()
Console.WriteLine("Done!")
Else
Win32.FreeConsole()
End If
When you run your windows form program and check the box it will automatically open the window and KEEP it open until you uncheck the box.
Add this class to the bottom of your program:
Public Class Win32
<DllImport("kernel32.dll")> Public Shared Function AllocConsole() As Boolean
End Function
<DllImport("kernel32.dll")> Public Shared Function FreeConsole() As Boolean
End Function
End Class
And be sure to add the Imports statement at the top
Imports System.Runtime.InteropServices

If you want to open a console window to interact with and when you close the console, that action won't terminate your windows program then you can add these two lines of code:
Dim myProcess As Process
myProcess = Process.Start("cmd.exe")

Related

vb.net Parameters Startup Form not hiding?

I am creating a application to be used with a touch panel device. The touch panel device comes with a standard windows OSK (On screen Keyboard). Whilst testing its been concluded that the standard OSK is to large and too complex for what we need it in. So I have built my own OSK. some of the feilds though only requier numeric inputs so I though of futher simplifying the process by creating a new form which hosts a numeric pad. so far this is all working. the idea is then to have the app which ask for diffrent inputs then to trigger the OSK application, say that the user wants to enter a phonenumber in one textbox I then want to start the OSK app using a parameter that trigers the OSK to start the NumericForm form first... this too I have working but the thing I can't get right is to hide the AlphabetForm I have tried the following method but am a little stumpt on how to get this right
In short its the Me.hide which isnt working as expected?
Private Sub AlphabetForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
#Region "Recive startup parameters (if any)"
Try
Dim OSKParameters As String = Command()
If OSKParameters = "OSKNUM" Then
NumericForm.Show()
Me.Hide()
Else
ShiftSelect = 0
End If
Catch ex As Exception
'Do nothing
End Try
#End Region
End Sub
Three possible setups, as described in comments:
► Using the Application Framework, override OnStartup and set Application.MainForm to a Form object determined by a command-line argument:
To generate ApplicationEvents.vb, where Partial Friend Class MyApplication is found, open the Project properties, Application pane, click the View Application Events Button: it will add the ApplicationEvents.vb file to the Project if it's not already there.
Imports Microsoft.VisualBasic.ApplicationServices
Partial Friend Class MyApplication
'[...]
Protected Overrides Function OnStartup(e As StartupEventArgs) As Boolean
Application.MainForm = If(e.CommandLine.Any(
Function(cmd) cmd.Equals("OSKNUM")), CType(NumericForm, Form), AlphabetForm)
Return MyBase.OnStartup(e)
End Function
'[...]
End Class
► Disabling Application Framework, to start the Application from Sub Main().
In the Project->Properties->Application pane, deselect Enable application framework and select Sub Main() from the Startup form dropdown.
If Sub Main() doesn't exist yet, it can be added to a Module file. Here, the Module is named Program.vb.
Module Program
Public Sub Main(args As String())
Application.EnableVisualStyles()
Application.SetCompatibleTextRenderingDefault(True)
Dim startForm as Form = If(args.Any(
Function(arg) arg.Equals("OSKNUM")), CType(New NumericForm(), Form), New AlphabetForm())
Application.Run(startForm)
End Sub
End Module
► If the OSK can be moved to UserControls, similar to what jmcilhinney suggested, run the default container Form and select the UserControl to show using the same logic (inspecting the command-line arguments):
Public Class AlphabetForm
Public Sub New()
InitializeComponent()
Dim args = My.Application.CommandLineArgs
Dim uc = If(args.Any(
Function(arg) arg.Equals("OSKNUM")), CType(New NumericUC(), UserControl), New AlphabetUC())
Me.Controls.Add(uc)
uc.BringToFront()
uc.Dock = DockStyle.Fill
End Sub
End Class

Create And Implement a Custom Form in VB.NET

I am trying to create a customized form class (CustomBorderlessForm) in VB.NET.
My Progress So Far
I created a new Class and named it CustomBorderlessForm.vb
I then proceeded to write the following code:
CustomBorderlessForm.vb
Public Class CustomBorderlessForm
Inherits Form
Dim _form As Form = Nothing
Public Sub New(form As Form)
_form = form
MsgBox("Testing: New()")
End Sub
Protected Overrides Sub OnMouseMove(e As MouseEventArgs)
MyBase.OnMouseMove(e)
MsgBox("Testing OnMouseMove()")
End Sub
End Class
Form1.vb
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim form As New CustomBorderlessForm(Me)
End Sub
End Class
Results of progress
A message box displays "Testing: New()" on load
Nothing shows on mouse move
As you can see, my problem lies with the events
Questions
Is it possible to create a form object and use that instead of the pre-populating form?
If so, can I give this form custom properties, such as, a border and some boolean values (shadow...etc), just like any other custom object/class?
What am I doing wrong in my current approach?
Why isn't the OnMouseMove being overridden?
Am I initialising the class wrong?
Can it even be done this way?
After creating a form you also need to show it. Change your logic to:
Dim form As New CustomBorderlessForm(Me)
form.Show()
Before you do that, I'd recommend changing from MsgBox to Console.WriteLine(), otherwise you can run into a fun/frustrating little cat and mouse game.
EDIT
Based on the comments, if, from VS you did a "Add New, Windows Form" you can just right-click the project, select property and on the Application tab change the Startup object to your new form. VS only allows you to do this with forms it creates for you (by default, more on this later).
If you wrote that file by hand (which is absolutely fine) you can perform the Show() like I did above and call Me.Hide() to hide the "parent" form. Unfortunately the Load event is fired before the Show event so if you place this in Form1_Load() it won't work. Instead you can use the Shown event like this:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim form As New CustomBorderlessForm(Me)
form.Show()
End Sub
Private Sub Form1_Shown(sender As Object, e As EventArgs) Handles Me.Shown
Me.Hide()
End Sub
Another option has to do with "Application framework". You can read about it here however it basically handles application events that other languages have to manually implement. If you go into your project properties you can uncheck the "Enable application framework" checkbox. This will give you more option in the "Startup object" dropdown. If you add the following code to your project one of the items in the Startup object dropdown menu should now be "Loader"
Public Module Loader
<STAThread()>
Public Sub Main()
Dim form As New CustomBorderlessForm(Nothing)
form.ShowDialog()
End Sub
End Module
You'll notice that the above bypasses Form1 completely. Also, instead of Show() I'm using ShowDialog() because otherwise the form shows and then the program ends.

How to run a console application without showing the console window

I have written an application with the following sub main:
Public Sub Main()
Dim Value As String() = Environment.GetCommandLineArgs
Dim F As Form
Select Case Value.Last.ToLower
Case "-character"
F = New frmCharacterSheet
Case "-viewer"
F = New frmClient
Case Else
F = New frmCombat
End Select
Application.Run(F)
End Sub
This is because I want to be able to install my app with three different startup modes based on the command line. I did have a form that did this, but this has made error trapping very hard because the main form just reports the error.
This console seems to work well but I don't want the user to see the black console screen at startup.
I have searched for the answer but most solutions are 'switch back to a windows forms application'. I don't want to do this though for the above reason. (I cannot use application.run(f) in a winforms start situation because I get a threading error.
I need to know either how to hide the console window, or alternatively how to code a main menu that will launch one of the other three forms (but making them the startup form).
Any help would be appreciated....
Try:
Private Declare Auto Function ShowWindow Lib "user32.dll" (ByVal hWnd As IntPtr, ByVal nCmdShow As Integer) As Boolean
Private Declare Auto Function GetConsoleWindow Lib "kernel32.dll" () As IntPtr
Private Const SW_HIDE As Integer = 0
Sub Main()
Dim hWndConsole As IntPtr
hWndConsole = GetConsoleWindow()
ShowWindow(hWndConsole, SW_HIDE)
'continue your code
End Sub
It has a side effect that the window will be shown and then immediately hidden
valter
"or alternatively how to code a main menu that will launch one of the other three forms (but making them the startup form)."
Start with a standard WinForms Project and use the Application.Startup() event. From there you can check your startup parameters and then dynamically change the Startup form by assigning your desired instance to "My.Application.MainForm". This will cause that form to load as if it was the one originally assigned to the "Startup Form" entry.
Click on Project --> Properties --> Application Tab --> "View Application Events" Button (bottom right; scroll down).
Change the Left dropdown from "(General)" to "(MyApplication Events)".
Change the Right dropdown from "Declarations" to "Startup".
Simplified code:
Namespace My
' The following events are available for MyApplication:
'
' Startup: Raised when the application starts, before the startup form is created.
' Shutdown: Raised after all application forms are closed. This event is not raised if the application terminates abnormally.
' UnhandledException: Raised if the application encounters an unhandled exception.
' StartupNextInstance: Raised when launching a single-instance application and the application is already active.
' NetworkAvailabilityChanged: Raised when the network connection is connected or disconnected.
Partial Friend Class MyApplication
Private Sub MyApplication_Startup(sender As Object, e As ApplicationServices.StartupEventArgs) Handles Me.Startup
If True Then
My.Application.MainForm = New Form1 ' <-- pass your desired instance to MainForm
End If
End Sub
End Class
End Namespace
Just go to Project Properties> Application> Application Type> and select Windows Forms Application
At this point your ConsoleApplication turns totally invisible, with no User-Interface.
I just want to add another solution although Idle_Mind has already provided an excellent one. This demonstrates that you can use Application.Run(Form) inside a WinForms app.
Public Class Form1
Private Shared applicationThread As New Threading.Thread(AddressOf Main)
Private Shared Sub Main()
Dim myForm As Form
Dim config = 2 ' if 3, will run Form3
Select Case config
Case 2
myForm = New Form2
Case 3
myForm = New Form3
Case Else
MessageBox.Show("Bad config!")
Exit Sub
End Select
Application.Run(myForm)
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
applicationThread.Start()
' immediately dispose Form1 so it's not even shown
Dispose()
End Sub
End Class

VB app not ending

I am using Visual Basic 2010 and I am makeing a simple login app it prompts you for a username and password if it gets it right I want to open a form then close the previus one but when I do me.close it ends the program and I can't go on
I am positive its working because I get the right password and username ut I can't close the first windows
I tried to hide it but when I do I cant close it and the program goes on without quiting and with a hidden form
I heard rumers that there is Sub that can control the x in the corner
if there is one that would probably solve my problem but I can't find it heres the code for the login form
Public Class Main_Login
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If TextBox1.Text = "My Name" And TextBox2.Text = "mypassword" Then
Contentsish.Show()
Me.Hide()
Label3.Hide()
Else
Label3.Show()
End If
End Sub
End Class
Then the Form if you enter the right login info
Public Class Contentsish
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Label1.Hide()
Timer1.Stop()
End Sub
End Class
how can I fix this problem?
Go into your project settings and set the application to close when the last form closes and not when the startup form closes.
edit: I just checked some of my VB.Net 2k8 code. What I do is create a new instance of the "child" form, do any initialization that I need, call .Show() on it, and then call .Close() on the current form (Me.Close()). Probably not the best way to do things, but it works for me. This is with the project setting I described earlier set. This allows me to exit from the child form or "logout" if needed.
Two other ways you can do this, in addition to Crags:
Load the main form first, then load the password from the main form.
You can use a separate vb module and use the Sub Main for the startup (you specify this in Project Properties, Application, Startup Object), then load the two forms from Sub Main.
So what happens if the login is incorrect? Sounds like you might want to show the login form using ShowDialog, maybe in your Main() before calling Application.Run(new FormMain());

"make single instance application" what does this do?

in vb 2008 express this option is available under application properties. does anyone know what is its function? does it make it so that it's impossible to open two instances at the same time?
does it make it so that it's impossible to open two instances at the same time?
Yes.
Why not just use a Mutex? This is what MS suggests and I have used it for many-a-years with no issues.
Public Class Form1
Private objMutex As System.Threading.Mutex
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
'Check to prevent running twice
objMutex = New System.Threading.Mutex(False, "MyApplicationName")
If objMutex.WaitOne(0, False) = False Then
objMutex.Close()
objMutex = Nothing
MessageBox.Show("Another instance is already running!")
End
End If
'If you get to this point it's frist instance
End Sub
End Class
When the form, in this case, closes, the mutex is released and you can open another. This works even if you app crashes.
Yes, it makes it impossible to open two instances at the same time.
However it's very important to be aware of the bugs. With some firewalls, it's impossible to open even one instance - your application crashes at startup! See this excellent article by Bill McCarthy for more details, and a technique for restricting your application to one instance. His technique for communicating the command-line argument from a second instance back to the first instance uses pipes in .NET 3.5.
Dim _process() As Process
_process = Process.GetProcessesByName(Process.GetCurrentProcess().ProcessName)
If _process.Length > 1 Then
MsgBox("El programa ya está ejecutandose.", vbInformation)
End
End If
I found a great article for this topic: Single Instance Application in VB.NET.
Example usage:
Module ModMain
Private m_Handler As New SingleInstanceHandler()
' You should download codes for SingleInstaceHandler() class from:
' http://www.codeproject.com/Articles/3865/Single-Instance-Application-in-VB-NET
Private m_MainForm As Form
Public Sub Main(ByVal args() As String)
AddHandler m_Handler.StartUpEvent, AddressOf StartUp ' Add the StartUp callback
m_Handler.Run(args)
End Sub
Public Sub StartUp(ByVal sender As Object, ByVal event_args As StartUpEventArgs)
If event_args.NewInstance Then ' This is the first instance, create the main form and addd the child forms
m_MainForm = New Form()
Application.Run(m_MainForm)
Else ' This is coming from another instance
' Your codes and actions for next instances...
End If
End Sub
End Module
Yes you're correct in that it will only allow one instance of your application to be open at a time.
There is even a easier method:
Use the following code...
Imports System.IO
On the main form load event do the following:
If File.Exist(Application.StartupPath & "\abc.txt") Then
'You can change the extension of the file to what ever you desire ex: dll, xyz etc.
MsgBox("Only one Instance of the application is allowed!!!")
Environment.Exit(0)
Else
File.Create(Application.StartupPath & "\abc.txt", 10, Fileoptions.DeleteonClose)
Endif
This will take care of single instances as well as thin clients, and the file cannot be deleted while the application is running. and on closing the application or if the application crashes the file will delete itself.