I've got 4 projects all running very similar multi-threading HTTPListener stuff.I wanted to make these functions common - in some module - but I'm having a hard time getting the AddressOf the "callback" passed in.This was the code in one of the 4 projects
Private Sub StartRequests(ByVal prefixes() As String)
If Not System.Net.HttpListener.IsSupported Then
DisplayInfo( _
[code].....
Here is a complicated, but possibly dumb question concerning adding projects together in the IDE in order to increase performance and share memory at the same time.I have written two distinct exe's. The first exe (file processsor) operates using three timers to perform communication between a hardware OEM proprietary ComServer and file output from the second exe. The second exe (work generator) simply outputs files on hard disk so that the "file processor" can process the commands in the order given. The first exe was written as a "background processor" to the second exe in a stand-alone fashion. There is a need to communicate data between the first and second exe that is time sensitive. The ComServer called by the "file processor" only allows one port to for communication to the hardware device that is a USB. The "file processor" is capable of extracting the data required but the existing technologies, such as RPC, IPC are too slow and or full of pitfalls. Microsoft's Memory Manger has found it easier to create multiple instances of the proprietary ComServer and assign the needed memory to the calling routine so that it can "scoot" memory easily in the garbage collection feature of the operating system. What this does is cause the mullitple instances that are created to "gang up" on the device either slowing its performance down, or causing time outs. [The second process is a custom 3-D graphical CAD/CAM. The first process is a machine interface. Although hind-sight is 20-20, it seemed more ideal to write this background or file processor independantly, as then it could communicate with existing as well as a custom CAD/CAMs.]
Simply writing the first processes' code into the second slows down the second process as a result of all the timer interrupts looking for work to do. (Mouse is squirrely, screen refresh is slow, etc.) I am only guessing here that the operating system's service of the more complicated single memory location is somehow interrupted more frequently for a larger project, than two smaller independant projects running seperately. I only know what I observer here. Interestingly, the two smaller projects running seperately seem to run fine.
Now for the dumb question. Is it possible to merge the "file processor" with the "work generator" in the IDE such that each process runs as independantly as two distinct apps, but at the same time, make it possible to share memory via one Module1.vb? So far, I cannot find a way for the "file processor" to see the "work generator's" Module1.vb, regardless of how many PUBLIC statements I issue in the code. In other words, what would be the steps after File->Add-> Existing Project to cause the "file processor" project with a form to start first, then drop to the background, followed by launching of the "work generator" second where each process shares the same Module1.vb?.
If this could be done, say through a compiler statement, or whatever; then this could make the Memory Manger folks happy, and provide for the speed required to operate real world processes? Basic computer science suggests a simple processor LD instruction could make data available to any application within a few clock ticks. Microsoft now longer allows direct memory access, or the ability to carve out a "stay resident" dll in memory where a memory location can be called for quick distribution information to all apps with just one call to a device.
I have started developing in vb.net 2008. I want to make a common module to validate all text boxes of my every win form. Common Validation I'm looking for are Length ( Size ) of text box value must not greater then that of field size, It must be of numeric, or alpha only, It must not be empty, if single quotation mark, covered with double quote mark etc.
View 5 Repliesis there a common way to test complex functions with several parameters with NUnit? I think it is very hard or impossible to test every condition.
I'm afraid the combination of parameters that isn't expected in the function is also not expected in the test.
So the expected condition will not fail but the unexpected.
I'm trying to use common Worksheet functions found in Excel 2003 (average, standard deviation, etc) from within VS 2008. See thinned down sample code below:
Code:
Imports Microsoft.Office.Interop
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code]....
When ran it returns "New cannot be used on an interface". Removing "New" returns "'WorksheetFunction' is a type in 'Excel' and cannot be used as an expression."
I've added a reference to the Microsoft.Office.Interop.Excel library v11.0.0.0, which I'm using in other places in the code with no complaints.
How can i make and use dll module in vb2010
View 5 RepliesI have an application that queries DHCP and pulls scope/subnet information. There are roughly 8k scopes on our network to query so reporting this data takes a little bit of time. I currently have this running on it's own thread and reporting to a progress bar so the applications doesn't seem inactive.
The DHCP api functions can report a total, a max read and a resume argument. This means that I can, in theory start 4 threads and have each thread read through 2k subnets, so it will only take 1/4 of the time to read all this data. Would I need to create four separate background worker handlers, do_works, runworkcomplete, report progress etc.?
I am trying to get a handle on SyncLock and multithreading, but I am having some trouble wrapping my head around exactly how it should be implemented. I have a Public Class Utilities with a many Shared Functions. I want to make sure that each function can only be executed when there are no other concurrent calls to the same function. So If I have 2 functions, A and B in a Public Class Utilities, what is the syntax so that a function "locks" while it is being executed, preventing any subsequent calls until the "locking" thread has completed?
CODE
Public Class Utilities
Public Shared Function A (ByRef i As Integer) As Integer
[CODE].............................
I know I need to wrap the statements of execution in a SyncLock block, but I am unsure of the scope of the parameter used with SyncLock...is it private to the function, class, etc? Can the same object be used to lock both functions if they are independent?
I have a Util module in my VB.NET program that has project-wide methods such as logging and property parsing. The general practice where I work seems to be to call these methods directly without prefixing them with Util. When I was new to VB, it took me a while to figure out where these methods/functions were coming from. As I use my own Util methods now, I can't help thinking that it's a lot clearer and more understandable to add Util. before each method call (you know immediately that it's user-defined but not within the current class, and where to find it), and is hardly even longer. What's the general practice when calling procedures/functions of VB modules? Should we prefix them with the module name or not?
View 3 Repliesif anyone knows if I can get a listing of all of the sub/functions in a class/module. Just the definitions (That is, the name, paramaters etc., but not the code).
View 3 RepliesEven though there are many examples of Invoke operations, I can't find something that works for me. (I'm using VS 2008, and working in VB)Here is what i have:
A main module with functions (thread 1) that starts a BeginRead for a TCPClient. When the callback function executes (on thread 3), I want to call a function from the main module, in the main thread. All I get even with Invokes is calling functions that always run in thread 3, not the parent thread.
I call:MsgBox("Function name: " & Thread.CurrentThread.ManagedThreadId)
in each of my functions do determine on what thread it is executed. At some point, from the infinite read callback function I will have to get a function to show a form, but that function gets caught in the callback thread and freezes, instead of running in the main thread.PS: the callback that I pass to the BeginRead of the TCPClient is a function, not a class, so I can't use raise events.All I need is to call a function to run in the main thread (main module) from another thread.
In developing a Windows Forms application (VS2010/VB) with several dozen classes and modules, I seem to have incorporated a variety of Win32 API function variations throughout my application, some of which seem to be duplicative/redundant. For improved code
[Code]....
I have a VB.Net interface that communicates with an Access 2k3 Database using this module:
Module MOD_ENGINE
'Declare Database connections controls
Dim con As New OleDb.OleDbConnection
Dim dbProvider, dbSource As String
[code]....
I want to call EngineConnect procedure from MOD_ENGINE module into popCboBox module so I can ignate the engine!
I am working on a MSDN project from 2007 it calls for a Common Dialog Control but I can not find it. Has this been deprecated and/or is there something to replace it? If not how can I access this in VS 2010 for a VB project?
View 16 RepliesI did this before but can't seem to remember how. How do I include a .COM tool into my IDE (like Common Dialog)?
View 2 RepliesWhat I am trying to do is have a class where the functions of the same name are both instance functions and shared functions.
Public Shared Function Get...(byval xx as xx)
and
Public Function Get...
The Public Function uses a Property xx created in the constructor, whereas the Shared Function has the parameters (byval xx as xx).
I'm using the WIA Aut. Library [URL] , trying to capture photos from 5 digital cameras (Nikon D90) USB-connected to my pc. Now, I partially achieved my goal, what I do is:
- loop through the attached devices, connecting to every camera;
- fotocamera.ExecuteCommand (WIA.CommandID.wiaCommandTakePicture) ;
- other image processing operations...
Everything works fine but... the workflow is camera1 -> connect -> grab pic. => camera 2 -> connect -> grab pic. => camera 3.....
[Code]...
I just put a button and a textbox on a form to try and learn to multi thread, i think i've done it correctly. but it still appears to freeze for a little bit just before it attempts to display the data. i think it's the invoking. Is it normal / have a done something wrong?
[Code]...
Sub Main() Try'process i files on their own thread
[Code]...
I'm running into a problem when I stop the debugger, the console window stays open, and I can't kill it via task manager.
explain to me why the 1st example gives me an error complaining about cross thread yada yada....but the second doesn't, and works? this is inside a worker thread function
[code...]
I understand the concept of needing delegates and all that jazz when working with multiple threads, but why give me an error if there's no invoke required anyway?
I would make a textbox in the form, then I add a Microsoft Speech Object Library reference. Then using Microsoft Speech, I would have the text-to-speech option. In the same class I would add this code:
[Code]...
I am developing a software that catches streaming data. Unfortunately, there is no pattern or sequence on how this data comes in. So what I have initially done is to catch then write to my MS Access DB. Unfortunately, while writing to the DB, I am missing some data that is streaming since writing takes a little bit of time before it goes back to the catching syntax.
I am planning to multithread the DB writing then just call it from my main program. Do guys know any website/tutorial where I can learn the basics for multithreading? I am using Visual Studio 2010. Or if ever, does any one of you have a sample program where I can just learn from?
I'm trying to execute a sub with multiple parameters on a separate thread, but I just can't get it to work, Here's my code
[Code]...
I'm writing a really simple file updater which downloads files off from a website and saves them. The download routine is working well, except that it freezes the project while attempting to connect to the host. Easily solved with threading except now when I try to access other form items such as text boxes, labels, form caption, it says I am not doing it in a safe manner and prompts an interrupt in debug. I did some reading on it and I'm still not sure what to do, I'm very new to vbnet and it is still a little confusing to me.
Error: Cross-thread operation not valid: Control 'Form1' accessed from a thread other than the thread it was created on.
Imports System.Threading
Imports System.Net
Imports System.IO
[code]....
The error occurs at: For i As Integer = 0 To txt_load.Lines.Count - 1..The project exists of 2 rtb's. One with a list of lines. The other will be filled with the converted lines. The main reason that I use it is that I want to use the app during the conversion. The second is that I want to learn how this works.[code]
View 9 RepliesRight now I have a Email class that has all the properties of an email to send it, and then a SendEmail function which takes those properties and uses them in the following
Public Function SendEmail()
'Exception handling
Try
[Code]....
The loop goes through each email in the array to process its email, however with the multithreaded function I cannot call
"EmailArray(i).ThreadSendBatchEmail()"
So how do I call an objects method when its on a different thread?
And I'm making it multithreaded so I can easily pause the process, and because the program freezes when the send() function is working, this would resolve that.
I have an issue with an app i am writing, i need to make a variable accessible to any module or class within the project but that cant be accessed outside of the app as it is accessing info the end user shouldn't have access to.
Ok, well a practice i have gotten into in the last few years is to declare a module on the same page as the main form and declare variables either friend or public (global variables). with my app public is not good so i tried Protected Friend but i cant use this within a module.
I tried placing it at the top of the main form but one of my classes can't access it, what would be the right way to do as expected. besides the main form i have 2 classes call them class1 and class2:- main interacts with both classes class1 accesses class2 class2 doesn't access class1
I want to make something similar to the listbox.children property. I know I can write this to return the children of the listbox:
[Code]...
I wanted to make a calculator. Its fully made and everything but I recently wanted to add more to it. Only thing I can't figure out to do is to make keyboard functions. Like, if I want to type in the numbers instead of clicking the buttons on the calculator to input it into the calc. [code]....
It works to a certain point but i found out that the timer input multiple integers when pressing a key so I thought of about turning off the timer and then having the timer turn back on somehow but that is as close as i can get.
I have a GUI VB application, and a seperate command line module. How can i run the command line module through the gui app, without binding / installing?
View 5 Replies