Defining A Class For Multiple Child Class Instances?
Feb 10, 2011
I have created a class for a Sports Facility. A facility has a Name, Status, Notes, etc as members of the class. This works well, I can create a new instance of an exisitng Sports Facility from the database, create a new instance, etc. All working well.What I am stuck on is accessing a list of Sports Facilities. I know I can create a new list by doing
Dim List As New List(Of Facility)
For Each fRow As DataRow In ds.Tables("Facilities").Rows
List.Add(New Facility(fRow.Item("FacilityID"))
Next
View 4 Replies
ADVERTISEMENT
Mar 29, 2010
I have the following problem. (VB.Net 2008)I have created a class (myFirstClass). In this class there are a lot of calculations being made wich gets fired by events in that same class.Now i want that same class to be able to fire more instances of itself. However i noticed that each time i fire an event from a Sub the program waits till the event is finished before going to the next line of code. This is a problem since i want the event wich fires a new instance of the class to fire it and forget about it.
View 7 Replies
Feb 15, 2009
I have a sub that runs on a button click which I want to create a new instance of a custom class and add it to a list of already created instances of this class. I want the result to be a List Of collection of all of my class instances.
My problem is that each time I run the sub, it simply 'overwrites' the first instance of the class and adds a copy of it to the list instead of writing a new instance. My code is along these lines
dim objFixture as new clsFixture
For n As Integer = 1 To intNoOfChannels
objFixture.SetChannelAddress(n, intCurrentChannelTotal + 1)
intCurrentChannelTotal += 1
next
lstFixtures.Add(objFixture)
View 7 Replies
Jan 31, 2011
I have the following code:
Option Explicit On
Imports System.DirectoryServices
Imports System.IO
[code].....
View 4 Replies
Dec 29, 2010
This is another one of my "I think it's not possible but I need confirmation" questions.I have a base class for a bunch of child classes. Right now, this base class has a few common properties the children use, like Name. The base is an abstract class (MustInherit)Technically, this means that everytime a child class is instantiated, it lugs around, in memory, its own copy of Name. The thing is, Name is going to be a fixed value for all instances of a given child. I.e., Child1.Name will return "child_object1", and Child2.Name will return "child_object2".
View 1 Replies
Jan 1, 2012
I have Class1 and class2 which is inside class1, VB.NET code:
Public Class class1
Public varisbleX As Integer = 1
Public Class class2
[code]....
View 1 Replies
Apr 11, 2009
I have a 'property management class' that contains several functions and properties. I have several other classes that use the 'management class' as a property to derive the value of several of its other properties.Is there a way for me to reference the outer class from the 'management class' functions without having to pass it as a parameter? I ask because several different classes can have this 'management class' as a property and am having a hard time typing the parameter.
View 7 Replies
Jan 2, 2010
I have a Parent Class Called Fuselage that containsfour child classes called Forebody, CenterBody, AftBody, and CrossSection. CrossSection classcontains objects common to Forebody, CenterBody, and Aftbody (example: width). How do I access thewidth property in CrossSection from within the classForebody?
Public Class Fuselage
Dim Forebody As ClsSection
Dim Centerbody As ClsSection
[code].....
View 6 Replies
May 3, 2011
When you create a Windows Service, you create a list of the services you want to start. The default is this:
ServicesToRun = New System.ServiceProcess.ServiceBase() {New Service}
Can you have multiple instances of the same Service class (that bind to different addresses or ports), like this?
ServicesToRun = New System.ServiceProcess.ServiceBase() {New Service("Option1"), New Service("Option2")}
Or will that cause problems? Should we use two different classes instead?
View 1 Replies
Jul 17, 2009
I have .cls files that have attributes for XML files, and i would like to refer to them in the main body of my code without having to define each one as a class in the code as this would be writing them twice. How can i refer to a .cls file in a vb.net form? If you're not living on the edge, you're taking up too much room
View 5 Replies
Sep 16, 2009
How do I define the controls from another class? Here is my code (highlighted) -
Imports System.Windows.Forms
Namespace Bryanlgh.Echo.Views
Namespace Bryanlgh.Core.Tasks
[Code]....
I also tried using Imports Bryanlgh.Echo.Views instead of Namespace and it also came up with 3 error messages -
1. Namespace or type specified in the Imports ' Bryanlgh.Echo.Views' doesn�t contain a public member or cannot be found.
2. Name 'cboPcpMd is not declared.
3. Name 'cboPhysicianPerforming' is not declared
How should I define these controls?
View 2 Replies
Mar 31, 2012
I have a problem that is frustrating me to no end, I have a overrideable function in a parent class, and the override function in the child class, like below:
[Code]...
When i debug, the value is produced, but it doesn't carry over to the parent class of ski.RetailPrice()what seems to be the problem here?
View 1 Replies
Sep 3, 2010
i am comfortable with class, namespace ,Sub ,Function ,Properties ...and so on. i studied about Custom Controls and Extension methods. There i found something new so called Attribute that are placed before classes and Functions definitions.[code...]
View 4 Replies
Jun 6, 2011
What is the side effects of defining a structure inside a class (name it X), and create a property inside that class of the type X?
View 1 Replies
Jun 24, 2009
I have a main form, and some sub forms, and each sub form can have some sub forms. When I have multiple sub forms open, and I try to get data from the parent form, it returns the data from the wrong parent form.For example I have two instances of Mainform.subform running. If I do something like this in a child form of one instance of the subform. It returns data from the other subform.
dim l = Mainform.subform.listofdata
Edit:I am using visual Studio 2008. Winforms, form designed using designer. In my mainform I am doing this
Protected Friend frmMain as Mainform
frmmain = new mainform
In frmMain I am doing this
Protected Friend frmsub as new Subform'
frmsub = new subform
[code]....
View 1 Replies
Nov 27, 2010
Is there some interface I can implement to allow basic comparisons and math to happen as it would an integer?
For example, let's say I have the following class:
Public Class Something
Public SomeBigNumber as UInt64
End Class
I would like to do something like this:
Dim SomethingA, SomethingB, SomethingC as New Something
....
If (SomethingA-SomethingB) > SomethingC Then
'Do stuff
End If
I was hoping to be able to implement some interface (if that is even the right term for it) that would return the UInt64 contained in the class for comparison and math, if possible.
View 1 Replies
Apr 28, 2009
I have a form whose purpose is to let the user to load map files.The form may manage a variable classes of maps, and each class have his own UserControl.To make it more user friendly, I added to each UserControl (different instances of the same class), a little map, showing a small picture of the map, and some data, as bound coordinates.
The problem is, that it looks really ugly. The maps are so big, compared with the rest of the UserControl (who contains just a button and a textbox to search for files).I wish to fix it, but I din not see an elegant way to include the pictures and info.I attach a form screen capture with two UserControl.I would like to get some tips for more experienced users. There are some guidelines?
View 5 Replies
Sep 3, 2011
info on creating instances of my own class at runtime. Simple project for family recipes but would like the option to add new recipes with new instances of my own food Item class at runtime. Creating my own class,no problem. Storing the data in an XML file, OK on that as well. My issue is creating new instances of different food item class as I use this program over time
View 13 Replies
Jun 17, 2009
I created a program a while back, in the traditional VB.NET way by drawing a bunch of forms. I have started playing around with creating the forms at runtime using classes. I have a placeholder form called frmStartup which merely calls the CreateLogin() sub from the CreateFormClass. The CreateLogin() sub creates a new blank form, then calls the grpbxLogin(), btnSave() and btnExit() subs from the FormElementClass which adds all the buttons and textboxes to the form. Within the FormElementClass, I have associated btnSave and btnExit with event handlers. These even handlers call subs from the DataProcessingClass. The event handler for Exit works just fine.I am having a problem with the Save event handler. Precisely, I don't know how to pass either the username or password from the Login form to the btnLogin_Click() sub in the DataProcessingForm. I have tried using Me. and frmLogin., but the program doesn't see either of those. If the Login form is an instance that is disposed of once another Sub is called, then it won't exist later on to call from. I have tried declaring variables and passing those along to btnLogin_Click, but no matter where I put it, the program doesn't see txtbxUsername.Text or txtbxPassword.Text. Not even from within FormElementsClass, which is were the boxes are created.Any ideas on how to pass variables in this case? I am not even sure what you would call this such as passing between classes, or passing between instances.[code]
View 9 Replies
Oct 20, 2008
I've decided to forget the d@mned custom code because everything I do with comes up with errors I don't know how to fix and it seems no one else does either. Or they do and they're keeping to themselves.
I put the functions that I needed to use in a class called MsgBoxOperations. The file name is MsgBoxOperations.vb In the report, up on the standard bar where file, edit, view, and all the other stuff is, is one that says report. You click that and go to report properties and it brings up where you can name the report and put in custom code...(hate custom code right now...) and where you can put references and class instances. Clicking on the Reference tab brings up wher you put in your references and classes.
In the classes area it asks for the Class Name, which I put in MsgBoxOperations, and the instance name of that class, this case mbo. I get that far and put in those two things and save it. Then I go to the textboxes where the values need to be. I put in the text box: =Code.mbo.GetStartDate
I've already tried taking the Code. part out and it screams that mbo isn't declared. So it does have to be there. I go to run the code and comes up with this error: QuoteError in class instance declaration for class MsgBoxOperations: [BC30002] Type 'MsgBoxOperations' is not defined.
I've posted before and still have received no help or someone tried to help but then stopped when their suggestion failed and then no one else wanted to help. I've googled this problem to the point where every link that it comes up with I have already clicked and found their information useless. I've got a freaking migraine because of this issue and have been in tears over it more than once.
View 14 Replies
Nov 1, 2011
I have an array of objects 2000 that are instances of a class. I want to alphebatise these objects by a detail of the class.
View 1 Replies
Jan 21, 2011
I have a .NET class, InstrumentConnector, that has an event, StatusChanged. I want to create several instances of this class (each class handles a separate file) and respond when the StatusChanged event is raised any instance. How would I do this in .NET? Do I want to create a List(Of InstrumentConnector) or a similar IEnumerable? How do I write the event handler to respond to a particular instance's StatusChanged event?
Here is the InstrumentConnector class and the module with the StatusChanged handler:
Public Class InstrumentConnector
Private _inProcessDir As String
Private _doneDir As String
[Code].....
View 2 Replies
May 24, 2011
What is an elegant way to create and initialise instances of a class that has several readonly properties? Passing all values in a constructor would not be very convenient.
The purpose is that instances are immutable after initialisation. However if the constructor is not used for initialising all the property values, then how can the readonly properties be changed from another class?
View 2 Replies
Jan 24, 2012
I'm a little out of my comfort zone here having programmed in VB6 quite a few years ago things have changed a lot since then.My issue is I have a class that I've built which works with no issues but I would like to be able to keep a 'handle' of some description on this class so I can also make adjustments to it's parameters when the user changes something. My problem is that I need to do this for an unknown quantity of these class instances.
In the VB.Net language how would I create an instance of this class that could be accessed by any Sub within the application and each instance created can be individually accessed by specifying some sort of identifier?
View 2 Replies
Oct 31, 2011
I have a class structure and am attempting to create an array of object instances from the class some instances are parents and some are children Code snippets,
Parent Class object
Option Strict On
Option Explicit On
Public Class cTransportItem
[code]....
View 1 Replies
Feb 14, 2012
I have a MultiThreading issue and conceptual question using Visual Basic (but it applies to almost all languages). [code]...
View 2 Replies
Dec 16, 2009
If Class X is within the scope of Class Y, is X a subclass of Y?If Class A is a sub Class of B, then is Class B considered a super class of A?if Class C inherits Class D is Class D a superclass or parent of Class C?if Class E extends Class F then we can consider Class E a child of F?if Class G inherits Class H and is within the scope of Class I then who is the parent of Class G? Classes that inherits Class J and classes that are within Class J are all sub classes of Class J?
View 1 Replies
Apr 17, 2010
if I have several of these movable PictureBoxes added to a Form (Form1) and want to display a selection rectangle only on that PictureBox, that is just selected,then I think I should use a flag to mark whether a PictureBox is selected or not. The flag could be used in paint event to decide,whether the selection rectangle is to be drawn or no .To add a flag property to the new class is no problem. But how can I set the flags in all other existing instances of the class, when it is set to True in the selected PictureBox?
View 1 Replies
Oct 27, 2009
I am having a problem with a and OOP class i made that contains a sub that creates random integers.
Problem is if i define two instances of this class and configure them(name in this case) then they both display different names but the random integers are ALWAY the same. in this case having the integers the same kinda kills the idea of the program.
Is it possible that the random part only every works for one class, but if .NET is fully OOP then this should not be possible... right?
Some of my Code (broken down to something smaller) i will display for obvious reasons.
Code:
View 11 Replies
Apr 15, 2010
I have put this code in the global form Inherits System.Windows.Forms.Form. And then in the form that will inherit this from the global Inherits MenuStrip. "MenuStrip" is what the global form is called. But keep getting this error: Error1Base class 'MenuStrip' specified for class 'Lesson2' cannot be different from the base class 'System.Windows.Forms.Form' of one of its other partial types.
View 5 Replies
