I need to make a subroutine run continuously in VB 2008

[petesquawk]

I need to make a subroutine run continuously in VB 2008.

Can I make a button permanently on? If this is possible, how can I do this? I can put all of the subroutines I want run inside the button click class.

[tlhintoq]

You don't do it as "a button always on"

Just make a loop.

while (true)
{
// true always evaluates to true, therefore the 'while' loop always keeps looping
// Do your continual stuff here
}

But you might want to do something a bit more sophisticated so you can stop the loop.

bool IsRunning = true;

// Then in your method
while (IsRunning)
{
// true always evaluates to true, therefore the 'while' loop always keeps looping
// Do your continual stuff here
}

// Later when someone hits the 'Stop' button you can
IsRunning = false; // Causing the next time through your loop to fail and end.

[petesquawk]

Thanks for your input.

I tried using just a while statement and it didn't like it because the while statement wasn't in a method body.

Public Class Form1
    Dim isrunning As Boolean = 1
    Dim COUNTER As Long = 0
    While (isrunning)
            RunContinuously()
    End While

    Private Sub RunContinuously()
        COUNTER = COUNTER + 1
        Label1.Text = COUNTER
    End Sub
End Class

I tried the following as well.

Public Class Form1
    
    Dim RUNNING As Boolean = 0
    Form1_Load()

    Private Sub Form1_Load()
        While (isrunning)
            RunContinuously()
        End While
    End Sub

    Private Sub RunContinuously()
        COUNTER = COUNTER + 1
        Label1.Text = COUNTER
    End Sub
End Class

[tlhintoq]

TIP: When you are writing your question, there is a button on the tool bar that wraps the [code] tags around your copy/pasted code. It helps a bunch. Its the button with a '#' on it. More on tags. They're cool. Check'em out.

[tlhintoq]

I tried using just a while statement and it didn't like it because the while statement wasn't in a method body

So... Ah.... Like.... Did you have a question?

[tlhintoq]

Must have been a late night.

Public Class Form1
 
    Dim RUNNING As Boolean = 0
    Form1_Load()
 
    Private Sub Form1_Load()
        While (isrunning)
            RunContinuously()
        End While
    End Sub
 
    Private Sub RunContinuously()
        COUNTER = COUNTER + 1
        Label1.Text = COUNTER
    End Sub
End Class

Let's see...

• Line 3 you create a variable called "RUNNING" but in line 7 you check against "isrunning" .
• Line 3 you initialize the variable to 0 (false) so of course when checked in line 7 the while condition fails.

One of the easiest ways to debug this sort of thing is to put a breakpoint in at the beginning of the section you want to check (line 7 in this example) then walk through the code one line at a time (F10 key) checking that each variable has a value you are expecting. It won't take long to see behavior you weren't expecting, like code execution jumping over code you thought would run.

[petesquawk]

Thanks for catching that wrong initialization.

I just need to figure out how to call a subroutine at the beginning of the program. It will not accept Form1_Load().

Public Class Form1
Dim isrunning As Boolean = 1
Dim COUNTER As Long = 0
Form1_Load()

Private Sub Form1_Load()
While (isrunning)
RunContinuously ()
End While
End Sub

Private Sub RunContinuously ()
COUNTER = COUNTER + 1
Label1.Text = COUNTER
End Sub
End Class

[tlhintoq]

It will not accept Form1_Load()

Why not? Do you get an error message? I use the Form_load event all the time (C#)

[petesquawk]

It said "Declaratio n Expected" when I went to run the code. That was the only error.

Link to other question rather than confuse this thread. [tlhintoq]

Thank you for your help.

[tlhintoq]

It said "Declaratio n Expected" when I went to run the code. That was the only error..

Ok... *Where* did it break when you got that error?

Public Class Form1
 
    Dim RUNNING As Boolean = 0
    Form1_Load()
 
    Private Sub Form1_Load()
        While (isrunning)
            RunContinuously()
        End While
    End Sub
 
    Private Sub RunContinuously()
        COUNTER = COUNTER + 1
        Label1.Text = COUNTER
    End Sub
End Class

In the properties pallet for Form1, click the Events button (yellow lightning bolt). Is this where you assigned the "Form_Load" event to your Form1_Load() handler? Did you even assign the handler to the event, or did you just type in the code for the handler thinking it would be picked up automatically and attach to the event?