Visual Basic

how to access PC parallel port through vb.net

10-Feb-05 5:00

Uhhh... your going to have to find a service yourself. Not all services work with all providers, so you're going to have to find various services and test them with your phone to see if they're going to work.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

FutureDream9-Feb-05 12:13

FutureDream

9-Feb-05 12:13

hi friends hi all Rose | [Rose]

?
for experts in VB.NET
please somebody helps me

am wana to develope web application (if i can say that ) to access a CAMERA through web
this camera fixed on two stepper motors which allowing the camera to move in the XYZ-axes
all these things connected to PC parallel port
so,i want to control the video from the camera and also the orientation of the stepper motor

please some body help me

my email is : dream2be2009@yahoo.com

my thanx for all

bye Rose | [Rose]

Dream2be2009@yahoo.com

Re: how to access PC parallel port through vb.net

Christian Graus9-Feb-05 12:30

Christian Graus

9-Feb-05 12:30

google inpout.dll

Christian

I have several lifelong friends that are New Yorkers but I have always gravitated toward the weirdo's. - Richard Stringer

Re: how to access PC parallel port through vb.net

j45mw26-Mar-05 15:40

j45mw

26-Mar-05 15:40

A company called Axis Communications has both video servers which you can attach a camera to and also video cameras with Pan, & Tilt which you can control through VB.net. They also have some very good sample VB.net code that shows how to do all of this.

You can't use the parallel port though, but you can access them through a URL address.

Invisible forms

H@is@here9-Feb-05 11:32

H@is@here

9-Feb-05 11:32

As anyone have sugestions how to start a invisible windows application?

Thanks.

Christian Graus9-Feb-05 12:30

Christian Graus

9-Feb-05 12:30

Invisible to who ?

Christian

I have several lifelong friends that are New Yorkers but I have always gravitated toward the weirdo's. - Richard Stringer

Dave Kreskowiak9-Feb-05 17:01

9-Feb-05 17:01

Define "invisible" and what do you want this app to do?

Normally, I'd suggest writing it as a service application, but you haven't supplied enough information to suggest anything, really.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

H@is@here10-Feb-05 11:42

H@is@here

10-Feb-05 11:42

OK sorry

I' am talking, about the property Form1.visible=False in VB6

For example

Starting a aplication with a system tray icon without showing the form at start in VB.NET .

Dave Kreskowiak10-Feb-05 13:10

10-Feb-05 13:10

WHich is it? VB6 or VB.NET? Are you trying to make a tray icon application?

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Virus Detecter16-Feb-05 2:55

Virus Detecter

16-Feb-05 2:55

Hello

Write the function in Module Main dont call form Call all function in module if your application doesn't containe getting input from user

Ishak

dynamic generation of crystal report

j45mw26-Mar-05 15:37

j45mw

26-Mar-05 15:37

I don't know if you ever got an answer you can use or if you finally figured out what to do, but if you want a form to start out invisible you set the Opacity = 0. If you want to see it again, set Opacity=100,

I have an app that I start with an "invisible form" (Opacity=0) and then I have it start another program which is visible. It works fine and has lasted a long time.

puneet_shadija9-Feb-05 8:49

puneet_shadija

9-Feb-05 8:49

well i am a student and new in vb.net. my requirement is such that,i have generated a datatable dynamically because my need is such that the number of columns in my table keep on variating depending on the user input...
actully i have several components per course and the no. of components keep changing and hence the number of marks given to students for the same components.
i am able to make the datatable on the fly in accordance to the user input but now i want to generate a crystal report... so that i can print it.
any help in this would be useful to me
thanks
puneet Confused | :confused:

Re: dynamic generation of crystal report

Dave Kreskowiak9-Feb-05 10:16

How to pass values to threads?

9-Feb-05 10:16

Help with what? You haven't asked a question specific enough to answer in a forum.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Zenly9-Feb-05 6:49

9-Feb-05 6:49

Hi,

I am trying to run a job that creates a new Thread but I don't know how to pass a value to this thread. I would like to pass a parameter to the TestThread(byval MyVal) Sub but if I try to add MyVal to "Thread(AddressOf testThread(myVal))" I get "AddressOf operand must be the name of a method..."

Here is what I have so far.....

Private Sub Button2_Click(...)
For i As Integer = 0 To 100
pvFile = "D:\Test\" & "test_" & i & ".txt"
Dim t As Thread = New Thread(AddressOf testThread(myVal))
t.Start()
Next
End Sub

Private Sub TestThread(ByVal MyVal as String)
Dim fi As FileInfo = New FileInfo(MyVal)
fi.Create().Close()
End Sub

Any help would be appreciated

thanks,

H@is@here9-Feb-05 11:39

H@is@here

9-Feb-05 11:39

It is not possible to pass values to threads.
You can do this:

Private MyVal as String

Private Sub Button2_Click(...)
For i As Integer = 0 To 100
pvFile = "D:\Test\" & "test_" & i & ".txt"

'You pass the value MyVal to a private field
MyVal="what ever"

Dim t As Thread = New Thread(AddressOf testThread)
t.Start()
Next
End Sub

Private Sub TestThread()
Dim fi As FileInfo = New FileInfo(MyVal)
fi.Create().Close()
End Sub

This is the easiest way

Zenly9-Feb-05 12:01

9-Feb-05 12:01

Thanks for responding.

Is there a way to make the "MyVal" private to each thread. I ran it and mutiple threads picked up the same filename which in turned caused an error because threy were trying to access the same file.

Thanks,

Dave Kreskowiak9-Feb-05 16:59

9-Feb-05 16:59

You'll have to encapsulate the threaded code in its own class.
Something like this (untested code):

Imports System
Imports System.Threading

Public Class ThreadWork

   Public MaxLoop As Integer

   Public Shared Sub DoWork()
      Dim i As Integer
      For i = 0 To MaxLoop
         Console.WriteLine("Working thread...")
         Thread.Sleep(100)
      Next i
   End Sub 'DoWork
End Class 'ThreadWork

Class ThreadTest
   
   Public Shared Sub Main()
      Dim i As Integer
      For i = 10 To 20
          Dim myThreadDelegate As New ThreadStart(AddressOf ThreadWork.DoWork)
          Dim myThread As New Thread(myThreadDelegate)
          myThread.MaxLoop = i
          myThread.Start()
      Next i
   End Sub 'Main
End Class 'ThreadTest

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Zenly13-Feb-05 17:08

13-Feb-05 17:08

Thanks for the sample. I tried it, though, and found that some of the threads were still, in my scenario, trying to access the same file. It works if I set a high enought sleep value.

I opted to pass the filenames at the thread name insteads. This way I do not need a sleep value and no thread would have the same name.

Private Sub btnCreateFile_Click(...)
For i as integer = 1 to 100
TheThread("D:\Test\File_" & i ".txt")
Next
End Sub

Public Shared Function TheThread(ByVal FileName As String)
Dim ThreadCaller As New Thread(New ThreadStart(AddressOf ProcessThread))
ThreadCaller.Name = FileName
ThreadCaller.Start()
End Sub

Private Shared Sub ProcessThread()
File.Create(Thread.CurrentThread.Name).close
End Sub

Do you see any issues with doing it this way? So far it's been working for me.

Thanks,

Dave Kreskowiak13-Feb-05 17:53

13-Feb-05 17:53

Thread names can only be 31 characters long. I hope your design takes this into account...

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Zenly14-Feb-05 2:33

14-Feb-05 2:33

Do you know of another property of a thread I could set to accomplish the same task without the 31 character limitation?

Dave Kreskowiak14-Feb-05 10:58