I'm trying to create a simple media player that will scan a directory for certain filetypes, add them to a playlist then play a random playlist entry - changing every x seconds.I figured this would be simple in VB and, to an extent it was. I have the code running that chooses the directory and plays the random file.I just need to now make this repeat every 30 seconds or so.I have all the coded attached under the sub for the 'open' function of the player so it's quite flat. I think I need to use a timer here, to trigger the routine to pick and play the media every 30 seconds?In doing this I think I need to break the variables out of the function I currently have as they need to be shared between the timer loop function and the central 'creating file list' function.
I'm having trouble - I'm no coder (as you'll tell!) and although getting this far was easy I'm now (I think) bumping into threading / variable scope issues which are a bit of a brick wall.I've tried making the variables public / global by declaring in the class rather than the sub but I get errors at runtime. Presumably because of how I'm creating the windows media objects? [code]
I'm moving from VB6 to VB.net and there are a few things confusing. In vb.net, your program just automatically has a form, now the form in in a class and so it may or may not be there. In vb6, the main subroutine controls program flow and I don't see that in vb.net. However, my biggest problem is that I have a com dll that has a connect class with events. I need to be able to access these variable outside of that class. I don't understand how to do that. I can't seem to declare public withevents outside of the class and in the namespace so it can be shared with other code. Its say "not valid" in Namespace.
So what is the best way to do that. Do I create a set/get property for the class that holds this value? And, if I do that, is the connect class automatically instantiated as a part of the COM dll? Right now I don't instantiate the connect class, I assume the application does. But I'm not sure exactly how the property of the class would be set...perhaps I would need to call the property set from the on-connection method. Anybody know what the answer to these two questions are and this 3rd one? How can I have a variable that has "events" have scope across the entire project?
how to declare scope for variables outside their class?
Here's what i have in a class known Create_User: Public Class Create_User Public conn As New SqlConnection(My.Settings.HotelConnectionString) Public usercmd As SqlCommand
[Code]....
How can i increase the scope of these variables to be used in another class? I dont want to keep declaring them again and again.
I have a public variable which seems to be going out of scope. I am confused as it has been dimensioned as a public variable: Public xlCell as As Microsoft.Office.Interop.Excel.Range
I originally had all my code in the same module in the same project and it was wrapped within a For/Next Loop (Example 1). I decided to clean up my code and make it more modular (Example 2). All the code is still in the same module in the same project.
Upon doing so, my public variable is not recognized in any of the private subs that I have created. I keep getting the following error: Message="Object reference not set to an instance of an object." When I test the variable using ?IsNothing(xlCell) in the Main Sub I get False in the main sub. this tells me te variable is recognized. However as soon as the Call SelectCaseSub() is triggered, I get a True value for ?IsNothing(xlCell). Why is this? Shouldn't this variable be in scope regardless?
where I should declare my variable when using forms and the scope in my test code.
In my code below I have declared variable x in my form1 which can be printed in form2.
But when I create a structure in form1, initialize an array of the type protorec and try to assign values to cards(1).firstname etc... I get a "declartion expected" error.
Why does it work for x but not for cards(x) my array of records?
I have put together the following code to illustrate the problems I've been struggling with:
Public Class OuterClass Private _OuterProp1 As Boolean = False Public Property OuterProp1 As Boolean
[code]....
I need to be able to refer to outer class properties and variables in an inner class, and I need to have a variable in one inner class set in a different class. I've tried Public, Private, Protected, Friend and all kinds of combinations of them, and I can't figure it out.
I'm working with legacy data, which often brings me one information splited in multiple columns. I'm trying to reproduce the following SQL query.[code]This own statement will run into the following exception:Variable 'line' of type 'SomeTable' referenced from scope '', but it is not defined. Any directions? I'm trying to avoid magic strings, but I'm always giving up to it (as using HQL the concatenation expression + like function works like a charm).
I have a windows application that need to process som quite time consuming jobs. In my first try i did all processing under the form thread. The result was bad response and update of the form due to the heavy jobs.To get around the problem with bad response from the form i created a new class "processing" where i put all the data processing. Then i instanciated a background worker where i in the "doWork" sub created a new instance of "processing".The "processing" class creates a timer from system.timer, and the timer drives the processing.On the Timer event Elapsed the timer starts a new thread from the thread pool.
My problem is now when i want to asynchronously close the background worker (with the corresponding function call what ever it is called ...) there is still a timer thread out there that causes exceptions for me.
1. How can i close my background worker and at the same time have the timer to be stopped?
2. Is there a way to synchronize the timer event so that the timer executes from the background worker thread?
I have some code and there are 2 errors which I don't understand I have tried all sorts...
1)The type for variable 'Index' will not be inferred because it is bound to a field in an enclosing scope. Either change the name of 'Index', of use the fully qualified name (for example, 'Me.Index' or 'MyBase.Index').
2)Function 'GetNewPhrase' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used.
This program was created with vb6 to find and remove empty folders. i converted this program to VB.NET code and it isn't working like it should.. it seems to stop scanning at 'C:\documents and settings' instead of scanning other folders in other directories...Does this code look right? I can provide the entire program if needed... I just want to know why it isn't scanning like it should. Btw im switching from vb6 and trying to learn vb.net.. vb.net is a lot different..
Private Sub ScanForEmpty(ByRef vFolder As String) Dim nSize As Integer System.Windows.Forms.Application.DoEvents() If bExit Then Exit Sub
[code]....
I get this message at the bottom:Warning5 The type for variable 'FolderObj' will not be inferred because it is bound to a field in an enclosing scope. Either change the name of 'FolderObj', of use the fully qualified name (for example, 'Me.FolderObj' or 'MyBase.FolderObj').
I want to create an array of timer in vb.net. My problem is that how will i raise the tick event for a particular timer, say mytimer(x).tick and inside the tick event there is also a button, say mybutton(x) which changes location every interval. for example:
public class blah dim mybuttons(20) as button dim mytimer(20) as timer private sub form_load(....) handles me.load for x as integer = 0 to 20
[Code]...
i dont know what to do next, all i want is to pass the button mybuttons(x) to mytimer(x) tick event, in which their index number are the same. i want to create one timer per button. how to do that? please help me and post example codes. i've researched the net but i cant understand passing variables, addhandlers, etc. i'm just new to programming object oriented.
This webservice is almost converted form VB to C#, except I get this error shown below on the DataRow arow object when I use it in the foreach statement below to populate the Results Class with a DataSet Object...
Error: A local variable named 'arow' cannot be declared in this scope because it would give a different meaning to 'arrow', which is already used in a 'parent or current' scope to denote something else
using System; using System.Web; using System.Collections;
Eg. ""vb.net" timer event trigger on purpose". This application is meant to run at all times to download a web page every minute. To avoid freezing the UI, I read that the best solution is to move the code from a While/Sleep loop to a Timer that will be triggered every minute. The problem I have, is that the user must wait for a minute before the event is triggered:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Timer1.Interval = 60000 Timer1.Enabled = True
[CODE]...
Is it possible to force this event to occur instead of waiting for it?
If I declare my object at the beggining of my page class, and instantiate it in a dropdownlist selected_index change event. Shouldn't this object be available thru out the entire page and also persist thru a postback? I lose the object in my selected date change event in my calendar.
I have a timer running like a scoreboard countdown timer. Is there a way that I can display that same timer into two windows forms (winforms) without resorting to properties?
I'm trying to work out a program where you can set up a variable amount of timers (like egg timers). Each timer works independently of the other (you can stop a timer, reset another, and so on, and the rest are not effected).I thought of using a single timer and then creating a custom egg timer class to handle the countdown, store the current time, etc, and use a collection of these classes inside a timer event (at the tick, do a for each to reduce the countdown on the classes by some milliseconds).Then I got to thinking: all of these egg timer classes in the collection with the for each loop may cause some accuracy loss (say, I add 50 egg timers).
Does anyone think the accuracy loss for updating all of the egg timers would be too adverse? Should I try running them on separate threads (have not thought about how yet), or will that make much difference?
I already created a button "enjoy button" that i want to move in a form when the "timer start button" is clicked. how do link the timer to the "timer start button" and make it move?
I'm trying to use the timer (not a Timer object) in a Do... Until loop. I want the loop to put a single variable into a label. When I do this it works and puts the value into the label (lblOxygenReading):
If btnGetOxygen.Text = "Get Oxygen Reading" Then Select Case True Case rdoColorWhite.Checked strCurrentColor = "White" Case rdoColorRed.Checked [Code] .....
It goes through the Do loop and the For.. next loop but doesn't change the label. Visual Studio doesn't show any errors when I'm writing the code, but when I run it, it hangs somewhere.
We have a question regarding VB.Net 2008. We are used control array in vb.net and third party timer controls. When handle received from external application to timer control event procedure, after this form becomes blank and controls disappear. What we have to do to persist the controls.
I already created a button "enjoy button" that i want to move in a form when the "timer start button" is clicked. how do link the timer to the "timer start button" and make it move?this is what i tried so far..
blankfirst-------------------------------------------------------------------------------Public Class MainForm Dim DX As Integer Dim DY As Integer Dim X As Integer Dim Y As Integer Dim Counter As Double Dim Y1 As Integer Dim Y2 As Integer Dim X1 As Integer Dim X2 As Integer------------------------------------then-------------------------------------------------------------
I'm trying to enable a timer from a SerialPort_DataReceived event. I can see that the timer is enabled, but the event does not fire. It's rather simple, but I need some help understanding why it doesn't run the code in TimerWait_Tick.
I used a timer in my user control now when Timer_Tick event is fired I want to raise an event like Ticked. I created:
public delegate sub myDel() public event myevnt as myDel in Timer.Tick
I used raiseEvent myevnt. I also raised the event from a button click. This event is handled in a windows form where the control is used, My problem is event is firing when the button is clicked but not firing from the timer.tick. Is there any problem from Timer.Tick.
I have a For Loop, how can I convert that by using Timer event. I want to use Timer so I can add a 5 sec, 10 sec and 15 sec pause (interval) for each every loop. [code]
