I am fairly new to vb and have created an alarm program. I have figured out how to write an xml file saving my variables. I can only save one set of variables currently. I would like to save multiple alarms to the xml and read back the xml as a list of alarms that the program is processing. Can someone lead me in the direction to calling the xml a list of alarms and how to read them into variables
maybe if i save the alarms sorted by date and time I could process them as they expire.
Question 1: What is the difference between "Background Worker" and "Worker Pool" as indicated within the MSDN samples provided.
Question 2: I noticed while using, AddressOf _Function_, variables cannot be passed; what would be an efficient solution to this?
Question 3: While using multithreading is it required to invoke before setting variables, or only form properties?
Question 4: While using System.Net.Sockets is it safe/efficient to use Application.DoEvents while waiting for new data; or would be using a Do While loop be fine without DoEvents since the action would be multithreaded? Note: there can be up to 2000-3000 sockets in use at a time.
I have a program that saves encrypted data to a file and each variable is separated by a ";". I then read the file though this command:
[Code]...
It places all the encrypted data to a Rich Text Box. I need to decrypt the data and place into variables. How do I read each encrypted piece up to the ";" then decrypt, and place into a variable? I've seen streamreader examples but I don't want to use streamreader unless there is a way I can still get the OpenFileDialog view to be able to select the file location.
After getting the file name I create a new filestream and load all the bytes from the FileStream into a byte array, now I need to get certain bytes and store them in fields like the second 4 bytes are the time the file was created. When storing these in the variables should I store them as bytes or as string/integers/etc.
Or have I done it completely wrong?
EDIT:Should I be doing this way instead of a filestream?
I've been using VBA quite a bit in the past to build userforms in Access, that used user-supplied data to custom-build sql statements on the fly, query data from a linked table, read that data into variables, perform calculations and spit out results onto the userform. Now I'm wanting to do some similar things in vb.net 2008.
I would use some code like this: Set MyRecordset = New adodb.Recordset MyRecordset.Open "SELECT * FROM Table1", CurrentProject.Connection, adOpenDynamic, adLockOptimistic MyRecordset.Filter = "ID = '" & Me.cmbAgentName.Value & "'" With MyRecordset [Code] .....
Whenever I try this, I get an error message along the lines of "Conversion from type 'Field' to type 'String' is not valid."
I am learning visual basic .net and I am attempting to translate some java source code to a vb.net project. The project reads mp3 details and then splits the file accurately according to the frameheader details etc.
I as part of the support VB code for a larger ASP project, I need to read back the existing data from an Access database, to see if user has changed a value.
I'm reading the existing data back into a DataView using the following function:
Public Shared Function GetPolicyStatus(ByVal intPolicyID As Integer) As DataView Dim strConString As String Dim conMyData As OleDbConnection
Last year (2010) I came across a FANTASTIC command that allowed me to take a string of variables with a common delimiter and break it all back out into separate variables (possibly an array) with one statement.
[Code]...
As long as the delimiter was a unique specifiable character, this one-statement command could break it out into elements. my memory and point me in the right direction.
I have code, shown below, that works all except for 1 thing: The variables being passed byRef get passed, but once modified in the else section of the "if me.invokerequired" code of RecordData, the variables are never updated in the calling function. To reiterate, the calling function does not receive the updated data that is in the variables custid and amt.When debugging, I see the data change in the else section of "if me.invokerequired", but once it returns from the callback the data is missing.[code]
I define some global variables of a class as follows:
Private Class MyClass Private var1 as Decimal Private list1 as List(Of string)[code].....
But I found that after this form is closed, all above variables, var1, list1, list2 still exist in memory. I thought they should be collected by gc since the form is already disposed as I confirmed.
Add: I have monitored half an hour after the form is closed. But these variables are not collected by gc. I have an automatic update procedure on the form which uses above variables.Since the above variables still hold values, the automatic update procedure is always called which causes exception. (One quick fix is to check if form.isDisposed in update procedure. But I do not think this is elegeant. Besides, these variables occupy memory.)
Does the memory used in declaring variables are reclaimed by the OS when these variables go out of scope?Does the memory used be released by setting thier value to nothing? if not, then how can I force the garbage collector to run or excecute at a certain/desired time..How about in Windows Forms..How can we make sure that the memory used in initializing and showing forms be released if those forms were closed?
I'm new in .NET programming.I have a class Form1 that includes Button1_Click event.Button1_Click creates a multiple Text Boxies at run time)Here is the class:
Public Class Form1 Dim shiftDown As Integer Dim counter As Integer
I am working on a project in VB 2008 and need it to do this:Read first line from text file (using Openfile)Enter line into textbox on formDo some other codeThen Read second linefrom text fileEnter line into same text boxand loop until we have gone through text fileI am not sure how to read line by line from text file then enter it in textbox. I can open the Openfile and get the filename and everything, but I just am not sure how to read from it or enter that line into the textbox.Here is what I have, its not much but its a start:
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim FileReader As StreamReader
I have a dictionary object (let's call it _do) I am using to cache some values for use in a multi-threaded program. I have a single controlling parent thread, with a timer function _doTimer() which can kick off child threads with a new instance of class MyThreadObject in each. My parent thread has _do as a property and with each time _doTimer() gets called, it may or may not repopulate _do depending on cacheflag settings. I pass a reference to _do to each instance of MyThreadObject and those threads at some point read the values of _do but DO NOT write to it.
What I want is to ensure that the child threads do not try and read _do whilst the parent thread is writing to it. Same thing but very slightly different -> I also don't want the parent thread to write to _do whilst the child threads are reading from it. However there is no problem with 1 child thread reading the values of _do at the same time as another child thread is reading the values - so ideally I do not want each child thread to completely lock out read access, only locking out Write access.. The code is roughly like this:
sql = "INSERT INTO Strings (String_Name, Long_Text, Short_Text, Alternate_Text, Multi_String_ID, Lang_ID) VALUES (?,?, ?,?,?,?)" Dim command = New OleDbCommand(sql, pConn) command.Parameters.AddWithValue("@webStringName", "String_Name")
[code]....
I am trying to create and INSERT statement with and OLE adapter. I had it working without paramtersm but now I am trying to add parms and am having issues with the syntax.Here is the code so far...
I got a problem dealing with variables: I would like in an if-then-else following If FZ1_KaskoTextBox.Text = 1 And Grundwert_Kasko <= 10000 And FZ1_BMComboBox.Text = 9 Then PraemieKasko_KFZ1_Var1 = 169.33 And PraemieKasko_KFZ1_Var2 = 169.33 Else But the variables don't get filled?! is there any possibility to fill two variables within one "then" ...
I have an ASP.NET application that I am developing. I'm using session variables within the app.In Firefox & Chrome, they all work.But in IE (ver 9), there's one variable that's not working. I'm not sure if it's a storage or a retrieval (or both) at this point. The variable in question that I'm storing is a List(T) type. It's the only one of it's kind that I'm using. Can't help but think there's a correlation there.One other old post mentioned the possibility that cache is causing the problem, but I didn't understand the answer very well.
Dim Rec_IDs As New List(Of String) Rec_IDs = Session("Rec_IDs") and Dim Rec_IDs As New List(Of String)
I have a CSV file with 35 fields. I have to read it into 35 variables. i know I can read the line, split it, write 35 assignment statemens. I am looking for an easier way (because I am lazy).
I'm looking for something like ReadCsvFile (A1, A2, A3, A4...A35) that will read a line, split it, and make all the assignments.
We have a couple of applications at work that need a reference to the license server set in the User Variables under the Enviroment Variables on the windows xp client machines(system properties, Advanced, Enviroment Variables). The problem is that both applications needs a reference to the same variable name and you can't have two with the same name. What i intend to do is to create a simple windows application with a button for each application that deletes the variable item present, adds a new variable item with the value needed for that application to be able to run and then run the application itself. This is just a temporary fix until we get a more permanent solution. The 'GetEnvironmentVariable' class in vb is not able to add or delete a item, maybe the WIN32 API could do the job.
Code: Public Structure StrFolder Public isActive As Boolean Public NameFolder As String[code]....
I would like to retrieve and print each variable name within a given structure (not its value). For example:
StrFolder(0).Name should print "isActive" StrFolder(1).Name should print "NameFolder" StrFolder(2).Name should print "URLIDNumber" StrFolder(3).Name should print "DateOfFolder" etc..
I would also like to know each type of an item within a structure. For example:
StrFolder(0).Type should print "Boolean" StrFolder(1).Type should print "String" StrFolder(2).Type should print "Integer" StrFolder(3).Type should print "String" etc..
I am writing an app to streamline my downloading and reading or manga, i usually download and manually extract each chapter into a specific location, based on what manga and chapter number it is. i then use windows picture viewer to read it.however, i can't work out a procedure that would take the manga name and chapter number out of the file name.i want to be able to pass the procedure a string containing the format that the file name is. e.g. "<title>_<chapter>_[IEM]" then i want the procedure to return the manga title and chapter umber into variables.for example, i pass the function "<title>_<chapter>_[IEM]" as the format string and [code]...
i have an int variable a = 8 and b = 2.How can I make variable a = 2 and b = 8 without using any other variable and making it generic so if you enter other numbers like lets say a= 10 and b = 5, you can still get a = 5 and b = 10?
We have these xml formatted .config files that come with all our ASP.NET programs. Well they have keys that need to be populated and I am unable to understand how to create a variable in xml and use it. The articles on variables in xml all seem to be talking about some other type of variable than I am familiar with. I am used to working in C or other programming languages.
I want to do something like MyVariable = "SomeString" <add key="Key1" value=MyVariable>
Is there an easy way to rank variables. Currently I have to compare each one to each other then try to eliminate one. Is there an easy code.Say x y z are all numbers. To find the highest I have to
if x > y and x > z then .... else y > x and y > z then.... else z > y and Z > x then...
this isnt' too bad with three variables, but if I have 10 or more it gets long... and then finding if x is first, finding what is the second highest is tough too
