I wanted to know if u define a dimension in a function or subroutine and that func/sub is called say 5 times, does the memory new block of memory get assigned to it every time the func/sub is run or does it use the one it got assigned the first time?
View 6 RepliesI 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?
View 13 RepliesI'm upgrading my VB6 project to VB.NET and I found one of the problem below relating to dimensional array.Here's my VB6 coding :
Private Function ConvertMatrixToBase0(ByVal MyMat() As Double) As Double()
Dim i, j As Long
Dim ConvMat() As Double[code.]...
When i port it over to VB.NET, i encountered error message 'ReDim' cannot change the number of dimensions of an array. for the line highlighted in red. And I suspect that VB.NET need to always define the exact dimension of the array during the declaration. But for the function above, for the array of 'MyMat()', I do not know what is the exact dimension every time it runs, and that is why i need to check the dimension of the array.My question is do we have any solution in dealing unknown dimension array in VB.NET? As in VB6, we can just define Array() instead of Array (,) in VB.NET.
how can i make sure i dispose of ALL my variables and sessions when i close the application?
i already have session.abandon(), but does it still keep all the other objects stored somewhere in the memory?
i've noticed that my w3wp.exe process keeps going up as i am testing my application. what is a good way to keep mem usage under control?
Assume I have a large dataset and I want to run a "like" function in the dataset eg column - NameIs there any way to run a like statement in a dataset.
View 5 RepliesAssume I have a large dataset and I want to run a "like" function in the dataset eg column - Name..Is there any way to run a like statement in a dataset.Is it possible with ASP.NET? I dont want to run a query to the database.
View 3 RepliesI don't use VB.Net very much, still mostly do VB6, but I am doing this project in .Net. I have a huge string of data, 168 Mb that I stream in from a file to a string variable. Then I have to perform a number of replacements on it before using the data to compile statistics. Because of the nature of the data, I can't break this up into smaller strings.
The problem is that I get a system out of memory error after a few replacements.
I've used both Replace(x,y,z) and X.Replace(y,z). The second one gets a little farther in the code before it crashes, but they both crash.
When I run it in the IDE, the IDE is using about 130 Mb of RAM, the Exe of the app is running about 350 Mb, and one svchost.exe runs about 300 Mb
Other than that there are no major RAM uses going on. The PC has an i7 980x cpu with 12 GB of RAM.
I have this relatively short function, triggered when the mouse is moved over a picturebox. When being called, it slowly increases the RAM and PF usage of the program which never recovers.[code]I just wanted to report back and say that I did solve this issue (more or less).I added a manual garbage collection call at the end of the loop and it kept the resources usage under control. It did seem to slightly slow the response time, but it's worth it to avoid the program hogging multiple GBs of RAM.
View 1 RepliesRead (search a value) in a non specific process memory. Write a value in the address found in the last function requested.
View 2 RepliesWhen I am writing a sub or function that does some calculations etc. I often need a loop or a integer variable to count.
An example:
''' <summary>
''' Compare elements with the new data and perform all necessary actions.
''' </summary>
[Code]....
As you can see, variables like timespan, nullCount and seconds are declared within this sub.
My question is, is it better to declare these in the class? I can imagine that would boost performance.
I have that code running into a windows service and the service seem to have a memory leak, something is wrong for sure. After looking at the whole code, I think it might be inside one of these function but I cannot seem to find where it could be.
[Code]...
I found this function for plotting a graph online somewhere. I am pretty sure it has a memory leak but cant figure most of the functions as I am new to VB and windows API. Looking for some quick tip on what I should be looking at.
[code]...
I have a VB Function (in Visual Studio 2008 with .NET 3.5) that opens up a connection to an Oracle database and queries the database for information. Apparently after some trial and error, I discovered when the SQL statement is being processed and filling the dataset, it apparently is taking up too much memory trying to complete the task. I'm running into System.OutofMemory exceptions and other unpleasantness.I'm wondering, is there some sort of program out there to measure memory consumption of your SQL code that is being processed in a Visual Studio application?
View 1 RepliesI have a VB Function (in Visual Studio 2008 with .NET 3.5) that opens up a connection to an Oracle database and queries the database for information. Apparently after some trial and error, I discovered when the SQL statement is being processed and filling the dataset, it apparently is taking up too much memory trying to complete the task.I'm running into System.OutofMemory exceptions and other unpleasantness.I'm wondering, is there some sort of program out there to measure memory consumption of your SQL code that is being processed in a Visual Studio application?
View 2 RepliesI am having trouble getting server variables remotely in VB .Net I need to basically mimic this PHP Function.
function showvar($string)
{
if(isset($_SERVER[$string]))
[Code]....
Atleast show me how to return one variable.
if this is a dumb question. I don't ever have to write anything in VB.NET.But I am passing variables named "name" to a function and sometimes it may be 1 name or 2 names, etc. I want to check in the function if its only 1 name don't add a comma, if it's 2 names add a comma. Is there a way to get how many "names" there are?
EDIT: Added my ode to make my question a little more clear. sorry for not doing it before.
My Code:Public Function GenerateCSV(byval str as string, byval str1 as string, byval str2 as string, byval GrpName as string)
[Code]...
I need the create a function with two variables Price1 and Price2 and the following rule:
if Price1 > Price2 at time t and not (Price1>Price2) at time t-1 Then
result=true
else
result=false
I should be able to use a loop to store the time t and t-1 Price1 and Price2 values.How can I do this in VB.net
I'm trying to make an application that calls a function to create a timer, but I cant use WithEvents or Private inside of a function or sub, Is there any way to do this?
View 5 RepliesI have 3 variables. Lets call it "a", "b" and "c". These 3 variables can "independently" have 3 different values. Lets say: "1", "6" and "10". when you think of them as combination; there are (3^3) 27 combinations. I am told that it can be done through the recursive functions. However i am not a good developer to handle with that. Would u please help me?
- 3 variables and 3 different values are simplified. In fact; the numbers of variables and different values can vary.
- i know only the language, visual basic in .net; please don't answer in other coding languages.
additional note: i am going to put the these combinations in the string format into a collection.. for example "1;1;1", "1;6;1", "1;6;10".. and so on..
I have a function which return the Dataset and my question is that, is dataset memory release automatic when function work finished if not please suggest me how i release memory in below sample question?
public function givemedataset()
dim keepme as new dataset
'grabbing record into dataset
return keepme
end function
Private Sub forumbrowsebtn_Click
dim getme as dataset=givemedataset
end sub
I have the following code:
Public Function StoreFields()
Dim Lockbox, Cash_Deposit_Date, Batch_Number
Lockbox = Xdocument.DOM.selectSingleNode("dfs:myFields/dfs:dataFields/d:tbl_GC100/@Lockbox").Text
[code].....
I have tested the variables in the Functions and the are correct.
I've been looking at threading to make my webapplications more responsive. I've found out how to thread a sub that takes no variables and doesn't return anything, but I can't find out how to achieve this for a function that takes variables and returns something. here is an example
[Code]...
i wrote a .NET function :
Public Function ExecuteSql(strSql As String, connectionString As String) As SqlDataReader
Dim conn As New SqlConnection(connectionString)
Dim cmd As New SqlCommand(strSql, conn)
Dim dr As SqlDataReader
[code]....
As you can see,this function return a datareader, so i can manipulate data as i like. The problem is: the connection remain open.Is there a command to 'close globally connection' ?
In VB 2005, I am calling a C++ DLL function that returns the address in memory and size in bytes of a jpeg image. How can I load that jpeg image directly from memory into a picture box in my VB form? I cannot afford to save it to disk first.
View 10 RepliesIm getting a problem with one of my programs I have made in visual basic.NET where it gives me a memory error when i debug the program in the IDE. the exact error is this: "Attempted to read or write protected memory. This is often an indication that other memory is corrupt". My program basically has a few forms with text fields on that get their text values from an access database on the same hard drive. Im wondering if im doing something wrong because my program just seems to eat up memory whenever it does anything. For example I have one form that has a combobox on it and when you change the drop down list selection it retreives a few strings from the database and puts them into the relevant text boxes, if you keep changing the selection then the memory usage (in task manager) just keeps going up and up. occasionally I get the error mentioned above when debugging but in my built version of the program it throws an exception everytime the memory usage gets past 49K.
Also I noticed when debugging in the "immediate window" frame I get the following message often:A first chance exception of type 'System. Invalid OperationException' occurred in System.Data.dll...Do I need to somehow be "releasing" the memory that is used to gather data once it becomes redundant?
I am using the following code
This error occurs :
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
Public Class FormRegEnumValue
[CODE]......................
QuoteSystem.AccessViolationException was unhandled Message="Attempted to read or write protected memory. This is often an indication that other memory is corrupt." Source="System.Windows.Forms"
Im designing a web browser and i continue to receive this error after going to about 3 websites it crashes with that error.
I have a BackgroundWorker object that I instantiated to perform a DB process on a background thread ansynchronously. I have event handlers for DoWork and RunWorkerCompleted. I can tell that the BackgroundWorker is disposing of itself because I added a message box into the Disposed event handler.Is it necessary to detach the event handlers to ensure that the memory is cleaned up and that there are not memory leaks?
View 1 RepliesI've noticed that every time I start a new thread in my program, the memory usage jumps about 1000k and it never goes back down. I have ensured that the thread is no longer running, and only one instance of my worker thread is ever running at a time. I am using ThreadPool.QueueUserWorkItem and ASyncOperation to get stuff done. The program starts using a Sub Main in a module that uses STAThread; I read that using STAThread instead of MTAThread makes it impossible for the Garbage Collector to get in and consider objects for garbage collection. However, when I change the STAThread to an MTAThread, the WebBrowser control in my frmMain cannot be instantiated.
I get this exception:
Code: An unhandled exception of type 'System.Threading.ThreadStateException' occurred in System.Windows.Forms.dll
Additional information: ActiveX control '8856f961-340a-11d0-a96b-00c04fd705a2' cannot be instantiated because the current thread is not in a single-threaded apartment. I do threading with the WebBrowser control, so will using MTAThread fix my problem? If so, how should I partition my code so that the WebBrowser control won't be affected by the above exception? I call the thread repeatedly with a timer (although only one instance ever runs at a time), and my program's memory usage starts at about 5000k and can jump to 300,000k+ depending on many times the thread needs to be called.