Class ComponentsContainer ' a component contains other components'
Inherits System.ComponentModel.Component
Private foo as New Component
Private bar as New Component
Protected Override Sub Finalize()
foo.Dispose() ' HERE ? '
bar.Dispose()
MyBase.Finalize()
End Sub
Protected Overrides Sub Dispose(disposing As Boolean)
[Code]...
I'm looking at some vb.net code I just inherited, and cannot fathom why the original developer would do this.
Basically, each "Domain" class is a collection of properties. And each one implements IDisposable.Dispose, and overrides Finalize(). There is no base class, so each just extents Object.
Dispose sets each private var to Nothing, or calls _private.Dispose when the property is another domain object. There's a private var that tracks the disposed state, and the final thing in Dispose is GC.suppressFinalize(Me)
Finalize just calls Me.Dispose and MyBase.Finalize.
There are no un-managed resources, no db connections, nothing that would seem to need this.
Is there a way to Finalize() or Dispose() a Module in VB.NET? Have a situation similar to the following and need to Dispose() itsUnManagedObject.[code]...
View 2 Replieshow do we implement Finalize to remove an object?i tried this:
Public Sub kill()
Me.Finalize()
End Sub
then this:
Dim g = New Test
g.kill()
MsgBox(g.ToString)
weird the object still exists, i don't get a NullReferencePointer exception
Recently I needed to compare a suggested pattern for IDisposable and object finalization with the auto-generated one we which VS2005/VB.NET provide. We have used the auto-generated one a fair bit, but after looking it the two side by side I had a number of questions about the VB.NET implementation..
[Code]...
Overall I am confused by the supposed added value of having an extended code-path that executes when Dispose() is called explicitly(as opposed to having a common path that is executed regardless of whether or not Dispose() was called explicitly). how it does anything other than delay the actual release of managed resources if Dispose() isn't called directly. In essence it seems to only work to make the managed resources unreachable in the object graph, orphaning them until the 2nd GC run rather than freeing them at a point where they are known to be no longer needed.
I looked at the Dispose() method in System.Data.SqlClient.SqlTransaction (using a decompiler):
[Code]....
Why does everyone say in forums that it is Rolling back in the dispose? Where does it rollback?
(1) I've read a lot of questions about IDisposable where the answers recommend not using Finalize unless you really need to because of the process time involved.What I haven't seen is how much this cost is and how often it's paid. Every millisecond? second? hour, day etc.
(2) Also, it seems to me that Finalize is handy when its not always known if an object can be disposed. For instance, the framework font class. A control can't dispose of it because it doesn't know if the font is shared. The font is usually created at design time so the user won't know to dispose it, therefore finalize kicks in to finally get rid of it when there are no references left. Is that a correct impression?
when i call GC.ReRegisterForFinalize(obj) and changed my mind, i could call GC.SuppressFinalize(obj) and remove it from the list of object that requests finalization. problem is that when i call GC.ReRegisterForFinalize(obj) twice, it registers the object twice in the finalization-listing. i need to remove the object from the finalization-listing but multiple calls of GC.SuppressFinalize(obj) could not remove obj from the list.also, why is it acceptable for this function to be called SuppresFinalize when after calling it Finalize still occurs?
View 2 RepliesI have a logging class that stores entries in a datatable dt. I then use SQLBULKCOPY to write that dt out to a sql table. Basic stuff. Problem is, I'd like to only call SQLBULKCOPY when there's say 50 entries in the dt. The problem is, what if I'm done (either intentionally or not, like if the code block that's using the log class throws an exception) with the logging object and there are still 15 rows in the dt?
View 1 RepliesI am comparing an alternative Dispose pattern to VS2005's default implementation. In doing the comparison I have found several uncertainties with the default pattern which have raised a handful of questions related to sub-class implementations and object Finalization.
[Code]...
why does finalize not get fired when i try to destroy a class until the application is exiting. i feel like because these objects were never actually finalized until the program is exiting that its somehow bogging down the operation of my app VS 2008?
View 1 RepliesI'm making a control and I am trying to finalize my design time properties grid. I have several List(of Class) items as public properties and when I click on the design time menu (while testing the control) there is the word "Collection" and a button with an ellipsis (...) that brings up a neat pop up with the buttons Add/remove and all of the public properties of the collection's class on the right hand side. Basically for a non-collection instance of a class (with public properties) I'd like a similar button to show up. I know I could put all of the properties in the main control class and group them, but I like the pop up box feature. Anyway to duplicate this? (think font grid item etc.)
View 3 RepliesHo to use xxx.DISPOSE() under VB.net
View 4 RepliesI have a program, and there is a timer to run it every 15 minutes. Every time it run, it will create a new exe / thread, (I monitor this thru an external software called TCPView). With the thread growing, it may slow down the performance, is there a way to dispose the thread before a new one is created?
Private Sub Processing()
Dim tmrThreadingTimer As Threading.Timer
Try
[code]....
I am having fun working with System.Threading.Tasks. Many of the code samples I see, however, look something like so:
Dim lcTask = Task.Factory.StartNew(Sub() DoSomeWork())
Dim lcTaskLong = Task.Factory.StartNew(Sub() DoSomeWork(), TaskCreationOptions.LongRunning)
Task.WaitAll(lcTask, lcTaskLong)
That's the extent of the sample.Tasks implement IDisposable, so obviously I'm supposed to dispose of them, but what if I just want to "Fire and Forget"?If I don't dispose, will I leak threads/handles/memory/karma?Am I using tasks "wrong"? (Should just use a delegate and leave tasks alone?)
Can I dispose in a "ContinueWith()"? (That seems like playing Russian Roulette.)[URL]..
When is it appropriate to apply the dispose method to controls?For example in a form that has five group boxes, once the first group box is used to gather user entries and is no longer needed, is it worth it to apply the dispose method to the first group box? Is it needed for local variables, for example a StringBuilder used within a private function which is only used while the function is executing?
View 1 Replies[Code]...
Here I am Clear the object using Dispose( Mycmd.Dispose()). Can I Use here Nothing ( Mycmd = Nothing?. Which is the Best ?
I attempting to dispose / close a startup form from a sub. Basically, I using the filesystemwatcher to watch for file creation, if the file is created, run some code and close the form.how to pass in some reference form. Using and new to vs2008. A bit of leap from VB 6.0.
Imports System.IO
Public watchfolder As System.IO.FileSystemWatcher
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[code]....
Hello, I have a WPF Window that I show with Window.Show(). When I click X the form closes. But it is still in memory and the GC never comes and cleans it up. Also I do not have any refrences/handles to it.
I am using the following code with the window:
Code:
Public Class PageWindow
Implements System.IDisposable
Public UserPressedExit As Boolean
[Code]....
I was experimenting with ways to get rid of some memory leaks within my application the other day when I realized that I know virtually nothing about cleaning up my resources. I did some research, and hoped that just calling the .dispose() would solve all of my problems. We have a table in our database that contains about 65,000 records. Obviously when I fill my dataset from the dataadapter, the memory usage can get pretty high. When I called the dispose method on the dataset, I was surprised to find out that NONE of the memory got released.
View 3 RepliesOut of pure curiosity, is there a way to free the memory used by a StringBuilder, other than the obvious MyBuilder = New StringBuilder and MyBuilder.Remove(0, Length) (although I guess the later wouldn't free anything, would it?)
View 6 RepliesI create class as Person and include a public sub Insert_DB I write down this code in form
vb
Dim MyPerson As New Person MyPerson.Insert_DB(Me.TextBox1.Text, Me.TextBox2.Text, Me.TextBox3.Text)
I tried to set Dispose to MyPerson (MyPerson.Dispose)but didn't show me Dispose
hi everyone i created a thumbnail dll for my file type my class dll create thumb for my files type but my class no dispose after create thumbnail this is my project : HPTShellExtThumbnailHandler.rar
View 5 RepliesOn the back of a Windows Form, I get a window DC, create a Graphics object with Graphics.FromHdc, and then dispose the Graphics object before releasing the DC.
Private Declare Function GetWindowDC Lib "user32.dll" (ByVal hwnd As IntPtr) As IntPtr
Private Declare Function ReleaseDC Lib "user32.dll" (ByVal hwnd As IntPtr, ByVal hdc As IntPtr) As Integer
Dim hdc As IntPtr = GetWindowDC(Me.Handle)
[code]....
Why did they do it this way?Should the DC be released before or after Graphics.Dispose?It is possible that the wrong order can cause resource leaks or memory corruption?
When you set a region equal to another, or set it equal to a new instance, do you have to call dispose on the region, or does VB do that? (I guess this isn't necessarily specific to regions)
ex:
'at some point in the code a region is created
Dim Rgn as New Region(SomeRect)
'....
[Code].....
If Rgn now points to the Rgns(0) clone, what happens to the original memory created by "New Region(SomeRect)"? Do I need to call dispose on Rgn before assigning it to the the Rgns(0) clone?
how do you correctly dispose a shape in vb.net ie when you draw a rectangle using the pen function how do I depose it so that it will disappear from the form, for some reason once its drawn if I draw a new shape it keeps the previous one and just overlays the new one and I use shape.dispose, and pen.dispose?
View 5 RepliesI used to always do the following:
con.close()
set con = nothing
Does con.Dispose() do both of the above 2 lines of code or do I do con.close() and then con.dispose()?
whats the difference of Me.Close and Me.Dispose...What code does releases memory resources that was used by ".show" command?Im currently creating a program and i just used both of them... is that ok?if it is ok... i know some commands have issues on what should i type first.. so what will i type first?
View 5 RepliesI Want to know garbage collector works in .net there is something heap and stack funda.so can u please tell me from where i get reference of whole funda of that.and i have another question is that Please see below the code.here i declare one dt and get
some data in it.and i don't want that dt after data come in text boxes.so in finally method i do dispose using dt.dispoe().
but after that i write little code to check whether the dt correctly dispose or not.so i check with if condition after disposing.you can check code given below for that condition.as per condition it gives me "Nikunj" Ouput in message box it meanse dt is not disposed after calling the dispose method.so can u please tell me why?And i Want to know about all resources which i used i want to know how can i free it.whether it is variable,object,datatable,datareader etc..... if it is any where with example then please give me link.and if it's from msdn then it's better. i want to know from Microsoft that
[code]...
I have Overloaded the Dispose method of System.Windows.Forms.Form Class in which I have written some extra code which I need to execute when object of Form Disposes. But when I create the object of Form in 'Using' statement, the 'End Using, statement do not execute my overloaded Dispose method. What should I do?
View 13 Replies