say you have a sub containing an io.streamwriter. That streamwriter is declared and used only inside that sub (and not as static). Should you still call dispose on that streamwriter or is it disposed automatically as it is no longer in use after that sub, until you call that sub again?
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I have several user controls which inherit from the following abstract class[code]....
View 1 RepliesI have a user control that inherits the FW ListView and I need to dispose of two objects when the form's disposing of it's objects. Here's what I've concluded already, am I on the right track?
[Code]...
I am implementing IDisposable for a class and while disposing there is a internal list of disposable objects. Should I be disposing those object by looping through them.
public Class MyDisposable
Implements IDisposable
private _disposbaleObjects as new List(of OtherDisposables)
[Code].....
In My application, I have an MDI form. From MDI form I open all forms as child forms. I have implemented IDisposable for all large objects like file stream DB connection etc. In the Form_Disposed event I dispose all unmanaged objects. After the child form is closed, all unmanaged objects are disposed but managed objects (controls and form) are not disposed and still in memory. I find it from .Net Memory Profiler ([URL]).
So I have write code to remove all event handlers of all controls and form. Now, When form closed, dispose is called and all event handlers and controls are disposed, but controls and form are still in memory.
I have a program like this.
Module Module1
Public Class Mstr
Public Property Prop1 As String
Public Property Prop2 As String[code]....
But it is not working as I expect it to. You can see it from.The DtlsB properties of all three DtlsA objects are having values from last iteration.
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?
I know that if i have a using block like
using myresource
return 0
end using
myresource will be disposed .
But if my using block is
using myresource
return myresource
end using
Will myresource be disposed?
I am wondering if a similar using block is causing memory lead in the app.
thanks
Should I call .Dispose() after returning an object that implements IDisposable? [code]In other words, is the object I return a copy, or is it the object itself?
View 11 RepliesIn my Zeal to get with the "Dispose" program, I implement a dispose pattern (still learning the ways and means of THAT) wherever it seems to make sense.I THINK I have the basic idea. However, I notice that, while Drawing.Brushes HAVE a Dispose method, when I call it, some sort of instability is created in Visual Studio itself, and i get the dreaded "Visual Studio has encountered an error and needs to close" splash screen, with no useable error information. SHould I assume that one should just NOT call dispose on Brush objects, or is there something I am missing here: [code]
View 7 RepliesI'm trying to fix all my project warning according to Microsoft code analysis (CA:XXXXX) One of the warning is "CA2000: Dispose objects before losing scope" My Code is:
[Code]...
I have 2 question, hope somebody give me an explanation: 1. Should a local variable call dispose method and set to nothing? 2. If some method have an arguments which it is a ByVal argument, it means a method create a new object? But If it is a ByRef argument, it means a method don't create a new object?
View 4 RepliesI am having trouble understanding the proper implementation of Dispose. While I totally understand the IDEA behind it (Ensuring that variable references to objects are released and free to be GC'd), I am not sure I am doing this properly.I try to call dispose on all items delcalred and used within a procedural scope when I am done with them (or even better, employ a Using block).When I declare Class-level items, I assume I should call dispose on them prior to destroying the class (During the "Disposed" event, right? which will occur when "Dispose" is called on my class?).As Declared in Class-level Declarations:
Public Class MyDisposableClass
Implements IDisposable
Protected mImgExpand As Image = My.Resources.ListCollapsePNG9x9_DK[code]........
When THIS class is instantiated within another class (Say, a form),I call "Dispose" on THie instance of this class during the form's "Close" Event. Everything seems to work fine. However,when I step through the code, things seem to go in a circle. We go from the close event, which calls dispose on the class instance, to the class instance dispose event, then back to the parent class disposed event, etc.
I am fiddling with the code here: [URL] I had a couple errors when I copied/pasted it into my project. I dimmed a couple variables, now the squiggle lines are gone, but I'm not sure how to call the functions in the project? Do I use a Lable or a TextBox? How do i make this work?
[Code]...
Accessing Dlls functions/objects using VBScript
View 2 RepliesThis is very basic about the layout of classes, subs etc. 1. Should all my subs & functions always be inside a class? I haven't used classes too much before, mostly just a bunch of subs in a form file. Now I downloaded a sample program which I want to develop. This has all the code of the form inside "Public Class Form1": [Code] The code is an example of use of the ZedGraph library. It produce a simple window with one graph/chart. Now I want to develop this code with several tabs, a dusin different charts, file I/O and so on. I'm ok with most of the specific coding, but my question is on the general coding;
2. Should I continue my subs&functions inside this form? inside this class? inside a new class? Earlier when I've NOT been using class, I can make global variables by placing the "Dim" outside the subs. This does not seem to work within a class. 3. Should I avoid global variables all together, or how is this done without always passing arguments?
Also I will make more forms, for program options etc. 4. Should these forms be coded as classes? or just subs&functions in a form? Obviously I'm not well trained on the proper use of classes and have trouble to find this easily explained.
i wanted to use streamwrite i use System.IO at the top of the code. What do i use if i want to use the E-Mail capabilities of the program?Does it matter what e-mail program u use as to what Process to call?I know that MAPI whould be there somewhere but unsure.
View 4 RepliesIf I have a class that inherits another class in which there are objects that are disposed in the dispose() procedure, do I use mybase.dispose? ex Class A inherits Class B. [code]
View 2 RepliesI'm familiar with Throw New Exception(), and how this causes an application to "break" with an error at the Throw line itself.But what I'm after is a way to throw the exception within a function, and for the application to break at the line which called the function - not at the Throw statement itself.Is there a way of doing this, but without having to wrap the function call within a Try-Catch?
For example:
1. Main code calls function "DoThis()"
2. DoThis() runs and throws an exception
3. Code breaks at "Call DoThis()"
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 Repliescodes to implement buttons to do the following
1. Pause a process/ action event.
2. Resume the process/ action event.
3. Stop the process/ action event.
4. Speak the time based on the clock.
Well I am a new to VB.NET, converting a legacy system to .NET world. Recently I have been reviewing the already existing code since I joined the project quite late in the team. I find that there are many shared functions (not shared class) inside many classes. I doubt this may create some problem if two requests ( i.e two different HTTP request to the same method as it's a WCF application, of course exposed methods are not shared but internally called methods are shared) comes to the same shared method and both the calls to the method may have different method parameters/arguments, overwriting each other's arguments. In short, if shared method has a list of arguments which is going to be processed, is there any chance of inconsistencies in the light of multiple access to the shared method via two http requests.
View 2 RepliesI have the same intention as in this question:
Automatically call all functions matching a certain pattern in python
But I needed the solution (if technically possible) in VB.NET. Is that possible in VB.NET ?
Visual Studio 2008, Standard Edition VB.NET I have only limited experience using the background worker, and all that I've done with it thus far was fairly straightforward and worked fine.
I am now looking to run a process in a background worker which calls various functions and/or subroutines, but of course it generates an error indicating that it's on the main thread (or something like that - I don't recall exactly, but that was the crux of it).
Does calling the Dispose method on a Windows.Forms.Timer call it's Stop method? Or should I stop the timer before I dispose it?
View 5 RepliesIm not exactly sure how to word this question, but I will give it my best shot.In a new program I am starting I would like to put all the code from a button_click event into a file (many others as well into different files), kind of like a class file in the sence of it being external.lets say I have a button called btnadd and it has some validation code in it Private Sub btnadd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnadd.Click
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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?
I'm fairly new to the concepts of OO programming - actually programming in general as I am still a student. I'm currently working as an intern in a department that has me coding a new structure that will probably be the base for all their applications to come. So I believe I have the idea behind OO down where you create "basic building blocks" and then expand, expand and expand, until you arrive at the most complex object (for the time being). I need to put all these "advanced" objects into one but how many is too many? Can I have 100 objects inside of this bigger object if it requires all these "parts".I really hope this question makes sense to everyone. I'm sure the answer is not going to be a definite answer either but I just need a rule of thumb to go by. I'd really hate to have 100 objects inside of 1 big one if there is a better design/programming technique. [code]
View 2 RepliesI want to know what are classes , objects , a namespace , subroutines,functions,methods,properties and differemce betweem byval and byref in your words.
View 18 Repliesi have created a panel wherein i am to insert the labels and data needed for printing. i have found a code to print labels and textboxes, however, datagridview is not included in the code.
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
PrintDocument1.Print()
End Sub
[code]....
