Creating And Disposing Classes?
Apr 14, 2010How can I dynamically initiate a "new" class?Basically I'm storing references to classes in an array and I want to create and dispose them on demand.
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Creating Classes And Objects?
Apr 10, 20111) Add a Private variable named _area2) Associate the _area variable with a Property procedure called Area3) Change the CalculateArea method to a Sub procedure. The method should calculate the area and then assign the result to the _area variable.4) Include a parameterized constructor in the class. The constructor should accept one argument: the side measurement. After using the Public property to initialize the Private variable, the constructor should automatically call the CalculateArea method.At this point I believe I've completed the first 2 steps for the Square method, but I'm not sure where to go from therHere is my code for the Square class and the Main Form, in tha order:
Public Class Square
Private _side As Integer
Private _area As Integer
[code].....
Creating A Class That Contains Other Classes/Objects?
Aug 27, 2010I'm wondering on how you would go abouts instantiating a class that contains other complex objects. for example an Payment Class which has Date,Time, etc.. and it also holds a reference to a paymethod object which has id,Type,Description etc.. How do you instantiate the payment class with all the other objects without one or the other failing, how do you create the payment class which doesn
View 4 RepliesCreating Depth Code For Two Classes
Feb 6, 2009How would you create depth code for two classes in visual basic 2008 (like if you wanted to put one picturebox behind another picturebox depending on what each picturebox's depth equals)?[code]I can't get my movement code and the image for the character object to work.
View 3 RepliesCreating Entity Classes With The O/R Designer?
Aug 15, 2011I am using the O/R Designer to create entity classes in VB 2010. I am observing different results for different database tables that I can't explain and more importantly, can't replicate the results that I want.Using server explorer, I have dragged a number of tables on the O/R designer surface, thereby creating the entity classes.
I have saved the project and can access the various entity classes in my project code. I first noticed a difference when changes made to object instances from some tables/entity classes appeared to persist while changes made to object instances from other tables/entity classes did not persist. These object instances are created, accessed, and changed using the exact same code patterns except for the object, class and table names.
I have been looking to see if there are any differences between the way in which the entity classes are treated, either in my code, in server explorer, or in the O/R Designer. I cannot find any. The properties of the entity classes indicate that all of the classes use the runtime methods for insert, delete and update. As far as I am aware, I have not knowingly made changes to these methods.
The ONLY difference that I find is in the file NameofClass.designer.vb. This is an automatically generated document. The partial class of those objects that appear to persist changes contains different code from that of other partial classes where changes to objects do not persist.In the declarations section of this partial class, the following lines appear:
<Global.System.Data.Linq.Mapping.TableAttribute(Name:="dbo.OrderofBattle")> _
Partial Public Class OrderofBattle
Implements System.ComponentModel.INotifyPropertyChanging, System.ComponentModel.INotifyPropertyChanged
[code]....
If I am right then I want to enable persistence in my other classes by causing this additional code to be generated for them. But how? why the code for this one class hase been generated differently than for all the others (actually it is this way for 2 out of about 15 classes). What setting or or selection do I have to make to enable this code to be created for my other entity classes during the automated process?
IDE :: Creating LINQ To SQL Classes: Using The O/R Designer?
Mar 27, 2009I am learningCreating LINQ to SQL Classes: Using the O/R Designer, the link is found below[url]...But when I Step #8 of Binding Controls on a Windows Form to Entity Classes says:8. Create an event handler for the Form_Load event by double-clicking the form. Add the following code to the event handler:
View 4 RepliesCreating Classes For Master Child Objects
Dec 26, 2010I have a Clients master object and then a number of child objects whose exact number is not known in advance such as Client-Contacts, Client-Payments etc, all of which have a one-to-many relationship with the Client master object.How do I define classes for such a scenario? Do I for instance create the master Clients class and can then I create an array of class somehow for child objects?
View 2 RepliesUsing Inheritance-Based Controls - Creating As New Classes (not UserControls) Inheriting From An Existing System Control
Oct 15, 2011I seem to be having a problem with controls that I am creating as new classes (not UserControls) inheriting from an existing system control. Everything seems ok while I create the control code, through to the compile (which is successful and adds the control to the toolbox) and dragging the control from the toolbox to the GUI surface. However, when I then debug or compile the project, I get a message such
[Code]...
Use LINQ To Filter Collection Of Nested Classes To Yield Dictionary Of Unique Properties Of Those Classes?
Jan 23, 2012I have two classes, one nested in the other. [code]Neither "Name" or "ID" are unique between operations and records.I wish to construct a dictionary using LINQ = Dictionary(Of String, Of List(Of Integer), whereby the keys are uniqe examples of Names in my collection and the values are the collective set of distinct IDs that are associated with those names.
View 2 RepliesVS 2010 Structure Classes So That The User Interfaces Though A Single Class While The Supporting Classes Are Hidden From Their View?
Jun 13, 2012How can I structure my classes so that the user interfaces though a single class while the supporting classes are hidden from their view? I think its best understood in an example:
Public Class MyInterface
Public Economic as EconomicClass
Public Sub New()
MyBase.New()
[code].....
So you might ask why am I even separating them? It's strictly for others who will be working with this interface. I need to funnel them though a logical structure:
interface.Economic.MyMethod
interface.Currency.MyMethod
etc
This way everything is already handled for them in the background and they only need to run the method they need. I don't know if I can have it both ways in VB.NET.
VS 2010 Calling Subs And Functions Within Classes That Are Within Classes?
Oct 24, 2009Here is some example code of what I mean:
vb
Public Class Form1
Private Sub Button1_Click(ByVal sender as Object, e as systemEventArgs) Handles Button1.Click
[Code]....
Across "Creating Classes In VB"?
Mar 31, 2010I have some question about Class I am doing all of my VB learning mostly thru this forum and via some tutorials, web searches and example programs. That being said, here I go.
From the MSDN website I came across "Creating Classes in Visual Basic"
I didn't know a Class could be created.So in your most non-technical laungage with the most layman terms posible. How would you describe a Class, Why would I need to create a Class?
[Code]...
Derived Classes Cannot Raise Base Classes
Jul 10, 2009I m trying to raise Click event of Textbox explictly but I m getting "Derived classes cannot raise base classes" error.[code]....
View 1 RepliesDisposing Of A Form?
Jan 13, 2010I have three forms (form1-3). my startup form is form3. This form calls form1.show. then form1 does form1.visible=false and also calls form2.showat the end form1 shows again.
View 4 RepliesDisposing Of An Array?
Jun 11, 2010I have created the following code block for use in my app (With the help of You, my online friends), it works ok.
The problem I now have is that I need to Despose of the Array from time to time an then later recreate it.
The "Despose" comand dont seem to work, How should I go about this?
Dim HoofGeregte As DataTable
HoofGeregte = HoofGeregteTableAdapter.GetData
Dim IngredientLabelLocationX As Integer = 42
[Code].....
'Using' Statements And Disposing Method
Nov 9, 2009I have a general query that I need clarifying by some intelligent boffins such as yourselves. I have the following code in a function:[code]Obviously the Dispose method will never be called on the site object or the helper object. This may be a stupid question but can I get an explanation as to how these objects actually get disposed of in memory? Is it just by the fact that the enclosing method they were created in has been disposed of?![code]
View 3 RepliesDataGridViewImageColumn - Disposing Of All Rows?
May 8, 2009I have a gridview where ALL cells have a value that is an image from the filesystem, but I need to access these files for a certain function and so I've been trying to create a method that disposes of all these images thereby freeing them up on the filesystem (was received permission denied errors). The following loop worked for the first row of images but I can't work out how to do it for all rows:
or Each c As DataGridViewImageColumn In dGV.Columns
c.Image.Dispose()
Next
[code].....
Disposing Of Dynamic Controls?
Mar 4, 2012Previous in my app, I've created dynamic controls and and named them blah0, blah1, blah2 etc. There will be a different amount created each time the user runs the app.I'm now trying to delete all of the controls but doing something very wrong. I've got the following
dim checkboxes = Controls.OfType(Of CheckBox).AsQueryable()
dim sPrefix as string = "blah"
for each checknum as checkbox in checkboxes
[code]....
When I execute the above, it only gets rid of every second control and I have no idea why. If I swap the dispose with a msgbox, the msgbox appears every time as I'd expect. It would seem that disposing of a checkbox seems to somehow requery the number available?
Getting Error While Disposing Form?
Jan 27, 2009why upon exiting a form which has the following code i get an "Incorect syntax near the keyword 'FROM' " ? The form is supposed to be disposed , so why does any code gets 'executed' ?
Private Sub Fill_Data()
Init_Comboboxes()
For Each Lesson_Name As String In SQLArrayFunction("SELECT LName FROM LessonNames", "LName")
ComboBox1.Items.Add(Lesson_Name)
[code]....
Splash Screen Not Disposing?
Sep 30, 2009i am developing an app in VS 2008 ->
i have frmMain as startup Form and frmsplash as splash screen now wat is happeneing is just my splash screen will not go off it remains there untill i click away from splash form somwhere on frmMain: One thing i have noticed and would like to share is: When i run my app. thru VS it works fine however when i run my myApp.exe splashScreen will not go off?
VS 2010 Some Doubts On Disposing?
May 17, 2011I have a class where there is some private strings to hold some data like name, address, etc. And also a private object of Process class. It also has an "AddHandler" method.
So, how to take care of the disposing part.
More info: I'm wrapping up this code into class.
CA2202 Warning About Disposing Objects
Sep 26, 2011I misidentified the problem. It is actually like this:[code...]
Code analysis complains about this because ms can be disposed twice. That will only be true if zStrm, which takes the memory stream as an argument to its constructor, disposes of the memory stream when it cleans up. That seems like a totally nutty thing for the disposer to be doing. Does it really do that? Would a class that takes another class as an argument, be so uncivil as to dispose of that argument?
I suppose it would, since the alternative would be that the memory stream might not be disposed at all if it was created in the constructor like this:[code...]
I guess the only real question is whether or not I have to worry about this?
Custom Controls Disposing & Memory?
Apr 14, 2010I've been working on a few large custom controls, and I noticed that when I use them, my memory starts ballooning. If I add a control at runtime, it increases the memory, but when I remove the control, it decreases less than it increased. However, it would stop balooning at some higher value. So if go back in forth between pages (which adds and removes the control), the memory would look something like this:
1,000K|5,000K|4,000K|9,000K|8,000K... 20,000K|25,000K|21,000K|25,000K|21,000K|25,000K... etc I know it takes a while for the GC to run, but the memory would stay consistantly high for long periods of time.
I tried writing a Closing routine, where when I called it, the control looped trhough its children and disposed all the internal controls, which seemed to help a little, but the memory after running the control and disposing was still much higher than before running the control. I also use custom event addhandlers. Should I remove all these as well. It would be nice if I received a little guidance on this.
Disposing A Global Font Variable?
Aug 13, 2010I have declared Fonts at class level to use it through my methods in that form. Form 'frmA' is shown with ShowDialog and when it closes or stops using fonts I'd like to properly dispose fonts.When I run code analysis FxCop it complaints with:CA2213 : Microsoft.Usage : 'frmA' contains field 'frmA.Font1' that is of IDisposable type: 'Font'. Change the Dispose method on 'frmA' to call Dispose or Close on this field...How to properly dispose globally declared fonts so that is "by the rules" and FxCop does not complain any more?How to 'Change the Dispose method on 'frmA' to call Dispose'?
VB.Net
Option Strict On
Public Class frmA
[code]....
Disposing Dynamically Created Pictureboxes?
Nov 30, 2010I am dynamically creating 12 picture boxes then click next and dynamically create the next 12 (in place of the first 12)
From what I can tell it is creating the next 12 I just can't see them. Do I first have to dispose of the original 12 first? if so how do I go about disposing of them?
Private Sub Pictures(ByVal DataXml As IEnumerable(Of XElement))
Dim song = DataXml
MsgBox("song index " & SongIndex)
[Code].....
Disposing Excel Process In VS 2008?
Aug 6, 2009There to all gurus,I'm trying to build an Excel generation aplication using VS 2008 and Microsoft Excel 2003, but some how the Excel process that i create it's stuck in the computers memory, and it's only removed when I END the VB Application.
[Code]...
Disposing Forms And Their Related Components?
Jan 20, 2009Class Structures
Public Class SBO_Collection
Private p_sample As SBO_Sample
[Code].....
Disposing Of Objects And Circular References
May 24, 2010I have a button which opens FormTest. When FormTest opens, it creates an instance of ClassTest and that class instance takes the form instance that called it (FormTest) so that it can perform operations on FormTest from the ClassTest class instance. So i have a form which owns an instance of a class which has a reference to the form.
[Code]...
Exception While Disposing Multilevel Databinding?
Jun 4, 2010I'm building an application in VS2008 (VB) and SQL 2005. I'm using databindings to bind controls to LINQtoSQL objects. If I bind a 'third level' property that can be null I get "Value cannot be null. Parameter name: component" error while disposing the control.
Steps to reproduce (8):
1- create TEST database in SQL
2- create tables like this:
USE [TEST]
GO
/****** Object: Table [dbo].[Table03] Script Date: 06/04/2010 12:26:44 ******/
SET ANSI_NULLS ON
[Code].....
VS 2005 Disposing A MDI Child Form?
May 27, 2010Quote:
Dim MyForm As Form
MyForm = New Form1()
With MyForm
[Code].....
i use these code to dispose a MDI Child form, but it automatically close the form.. What should I do?