.net - Using Object Class As An Array?
Dec 19, 2010like every class in .net does Arrays also inherit Object?
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Object Reference Not Set To An Instance Of An Object With A Class With An Array Of Classes As A Member?
Aug 6, 2010Here is the structure that I have:
Friend Class StandardFormatFile
Friend fileType As String
Friend numberOfSeries As Integer
[code].....
VS 2008 Adding Class Object To List Or Array In A Different Class
Jun 21, 2010I am trying to create an list or an array of a class.Here is my "Ingredient" class that I am trying to create a list of:[code]In my "recipe" class, I am want to create a list (or array) and I am drawing a big blank on how to do it. Can anyone point me in the right direction?
View 2 RepliesUtilizing A Centralized Class object That Needs To Call Another Class Object?
Jun 7, 2010I am utilizing a centralized class object that needs to call another class object. The program itself will do something like the following
sFieldValue = CentralObject.ObjectHandler(1, TestFunction, "FunctionVar,FunctionVar2,FunctionVar3")
In the central object I have a function
Public
Function ObjectHandler(ByVal ObjectType
As
Integer,
[code]....
Flattening An Object Hierarchy Using A Shim Class - Initializing Derived Object Properties From The Base Object?
Jul 10, 2010I am somewhat new to object oriented programming and am attempting to flatten a Linq object hierarchy by using a shim class.how to initalize a derived class with property values from a base class?I have two objects, a base object with about 100 properties, and a derived object which inherits from the base object and adds a few additional properties beyond those of the base object. My simple constructor creates the derived object, but I am looking for a way to initialize the derived object properties with values from the base object.Right now I am using reflection to iterate over the properties individually and I suspect there may be a better way. The following example shows my shim class constructor for the derived class, and two properties:
newProperty1 - a new string property of the derived class
flattenedProperty2 - a new string property of the derived class, copied from a 2nd-level object of the base class
Code example:
Public Class derivedObj
Inherits baseObj
Private _newProperty1 As String[code].......
Is this the correct constructor approach to flatten the object hierarchy using a shim class? My second question relates to initialization of properties in the derived class. The constructor above creates the derived object, but what is the best way to initialize the derived object properties with values from the base object? The following code uses reflection to iterate over the properties individually, but I suspect there may be a better way.
Code example:
' property names are in the string array fieldNames
'baseObjQuery is an ienumerable of baseObj
'derivedObjList is a list of derivedObj[code].....
Is there a simple way to initialize values for the properties in the derived object based upon the values of the common properties in the base object?
Access To Object Passed ByRef In The Constructor Of A Class Through Another Part Of The Class?
Aug 18, 2009I have some classes, BsfciFile and StudyFlashCard. Bsfci is the extension to which I save my set of flashcards in an INI format. I am currently working to transform my code from using Windows API calls to access the INI to using a IniFile class that I found on the internet. I would like the BsfciFile to have a Array of StudyFlashCard objects, but I would like the StudyFlashCard class to use the IniFile class object contained in the BsfciFile class. I can pass the IniFile from the BsfciFile class to the constructor for the StudyFlashCard class, but I want it to modify the same IniFile as the BsfciFile class has later on.
[Code]...
Instantiate Object From Class Using String Variable For Name Of New Object?
Aug 11, 2009dim myCollection as new Specialized.StringCollection
dim myFoundThings as new ArrayList
dim index as Integer
dim newResultMemberName as String
[code]....
This is part of some code that will run without user interaction once it's spinning away, and I need to create a unique object from some items found in a StringCollection, naming the objects using information found in the strings stored in that StringCollection.
Iterate Through Class / Object Properties - Saving Them Each To Another Object
Dec 15, 2011I'd like to have something like:
[Code]...
Type Conversion From Webservice Object To Class Object?
Jun 15, 2009i've created bunch of classes. i have webservices which reference these classes and contains the classes as parameters and return objects.when i call the weservice, i have to convert the class to the webservice object else i can type conversion error.is there a generic way to convert between these types without having to assign the values by hand?
for example
public class person
fname as string
lname as string
end class
[code]....
i would liek ot be able to call the web service and return the data type back and have a generic coversion instead of as above in stead of:
dim wsPerson as wsReference.Person = ws.getperson()
Class With Class Properties: Object Reference Not Set To An Instance
Aug 19, 2009I have a class in which some of the fields are also classes.
I can put values in the "normal" properties, but in the others when o try to assign values it gives the: "Object reference not set to an instance of an object"
But the code compiles fine.
dados_Defenicao = New ServiceReference1.draftClaimEntryDefinition
dados_Defenicao.arCode = "123"
dados_Defenicao.claimMarket.warrantyType = "w" - Here it gives the error
Get Base Class Object Reference Outside The Class's Definition?
Dec 10, 2010If we are within the derived class then ofcource we can use MyBase keyword to access base class's object reference . That's fine , how can we take that base class's object reference outside that derived class's definition.My following code will explain what i want . Actually that is giving error right now, but it is explaining my requirement .
Public Class Base
Public x As String
End Class
[code]....
Actually there is error in ReadOnly Property BaseReference's Getter . Error is "Error 1 'MyBase' must be followed by '.' and an identifier. " how can i get base class object reference in Main method ?
IDE :: Class Files. Same As Namespace Or The Same As The Class Object Inside?
May 22, 2009If my namespace is Company.Application.EDI.Acknowledgement and if I stick with theprogramming practice of one class per file then should my class be saved asacknowledgement.vb? Are there any gotchas that will come up?
View 5 RepliesReference A Parent Class Object From A Child Class?
Jan 2, 2010I 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].....
Create An Object From The Class - Use The Object To Interact With The SQL Db?
Apr 12, 2006I am developing an IT Asset Tracking application using VB 2005 and SQL Server 2005 Express edition. Will I need to create classes to represent objects such as Computers, Printers, Scanners/Faxes, Contracts, Purchase Orders etc or are there any other approaches.For example, if I am correct, I will have a class called Computer and its properties will include Make,Model,CPU,Hard Disk,Memory etc. Is this the right approach.
Computers can be split up into Desktop PC's, Servers and Notebooks. Would I have to create separate classes for these as well or would they be ok under the Computer class.Once I create an object from the class, how can I use the object to interact with the SQL db.I am a beginner to VB.NET 2005 therefore I am slowly getting to grips with OOP.
Object Array To Byte Array - Marshal.AllocHGlobal Fragmentation Query?
Jun 14, 2011I didn't think it fair to post a comment on Fredrik Mörk's answer in this 2 year old post, so I thought I'd just ask it as a new question instead..NB: This is not a critiscm of the answer in any way, I'm simply trying to understand this all before delving into memory management / the marshal class.
In that answer, the function GetByteArray allocates memory to each object within the given array, within a loop.Would the GetByteArray function on the aforementioned post have benefited at all from allocating memory for the total size of the provided array:
Dim arrayBufferPtr = Marshal.AllocHGlobal(Marshal.SizeOf(<arrayElement>) * <array>.Count)
I just wonder if allocating the memory, as shown in the answer, causes any kind of fragmentation? Assuming there may be fragmentation, would there be much of an impact to be concerned with? Would allocating the memory in the way I've shown force you to call IntPtr.ToInt## to obtain pointer offsets from the overall allocation pointer, and therefore force you to check the underlying architecture to ensure the correct method is used*1 or is there a better way? (ToInt32/ToInt64 depending on x86/64?)
*1 I read elsewhere that calling the wrong IntPtr.ToInt## will cause overflow exceptions. What I mean by that statement is would I use:
Dim anOffsetPtr As New IntPtr(arrayBufferPtr.ToInt## + (loopIndex * <arrayElementSize>))
I've read through a few articles on the VB.Net Marshal class and memory allocation; listed below, but if you know fo any other good articles I'm all ears![URL]..
Writing Data From Array In One Class To A Listbox In Another Class
Jul 26, 2011I'm designing a small GUI Windows program that allow staff at a cinema to reserve seats for customers. There will be a total of 60 seats in the cinema. I have two classes in my program:-
1.) MainForm.vb - used for I/O actions and user interaction
2.) SeatManager.vb - used to hold and handle the background methods and functions that make the program work
Here is the code for my MainForm.vb class thusfar:-
Public Class MainForm
Private Const m_totalNumberOfSeats As Integer = 60
Private m_seatManager As SeatManager
[Code]....
Basically, when the program opens, the lstReservations list in the MainForm class will be populated with a total of 60 (m_totalNumberOfSeats) entries to represent 60 seats. Each of these seats will contain the index number from the array m_nameList; this index number (+1) will represent the seat number and then in the lstReservations list, after the seat number, I'd like it to contain the respective entry from the m_nameList array. As all entries will be held in RAM, when the GUI is opened, all m_nameList array entries will be empty. As the user uses the program, they can highlight a row in the lstReservations list and then use the GUI textboxes to enter the customer's name which will then be populated into the respective array entry.
how to, when the GUI opens, ensure that the lstReservations list takes all of the blank entries from the m_nameList array and from there, I can highlight a row to carry out further methods on?
Generic Class Array - Reading In A Excel File And Extract Data To Store In A Array
Sep 9, 2010I want to reading in a excel file and extract the sCodenumber sDescription ans the sStatus and store them in a array : StatusComposeArray(5200) As MyCompose. After this I need this array for comparing outside this class. But as can you see the array is defined inside the sub: ReadingIn_ExcelFilesCompose [Code]
View 2 RepliesConvert C# Class's Byte Array Values Into Integer Array?
Jun 22, 2010A c# class's single dimension byte array contains socket level instrument sensor data as per:
public static byte[] frameData
Creating An Array Of A Class, And An Array In The Class?
Jan 20, 2009It's been a LONG time since I messed with VB, and I'm messing around with VB 2008 now.I'm trying to make a custom class with three variables,
ID (String)
Title (String)
Comments (Array of String)
[code]......
Passing An Array Of Integer To An Array Of Object In A Function
Mar 4, 2012I am creating a dll with all the functions and subroutines that I use all the time and I decided to create a function that I can pass different types of array to so the function obviously (or not) would have an array of type object. Now I no you can pass any type into an object type but when I pass an integer array into an object array I get an error.
value of type '1-dimensional array of integer' cannot be converted to '1-dimensional array of object' because 'integer' is not a reference type.
Shared Function CompareArray(ByVal FirstArray() As Object, ByVal SecondArray() As Object, Optional ByRef ErrorMessage As String = "") As Boolean
Dim IntArrayOne() As Integer = {1,2,3,4,5} Dim IntArrayTwo() As Integer = {1,2,3,5,6} Dim IsSame As Boolean = False IsSame = CompareArray(IntArrayOne(), IntArrayTwo())
Creating An Object Array Of Different Object Types?
Mar 29, 2010I am having some trouble creating an object array of different object types. Here is what I have so far:
Public Sub New()
Dim b1 As New Book("Book Title 1", "Gold Book Publisher", 1.0, "Bob Jones", "192DJDJD212", "01/02/10")
Dim b2 As New Book("Book Title 2", "Gold Book Publisher", 1.0, "Bob Jones", "192DJDJD212", "01/02/10")
Dim b3 As New Book("Book Title 3", "Gold Book Publisher", 1.0, "Bob Jones", "192DJDJD212", "01/02/10")
[code]....
If I define the array As Book (Public publicationArray(6) As Book) or Magazine (Public publicationArray(6) As Magazine) I am able to access the properties of that class but not both. I think I need to define a type for each array instance but not sure how to do this.
Return An Array Of Object Interface's Rather Than An Object?
Mar 4, 2009I have an interface that describes an specialized list in my application...
[Code]....
Is there a way to make an interface serializable, or am I going to have to convert each of my objects into a concrete class implementing the interface, and then return that class?
Difference Between Using The 'array' Class In VB And Just Declaring An Array Like Normal?
Mar 12, 2010What is the difference between using the 'array' class in VB and just declaring an array like normal. In other words, what is the difference between:
Dim numOfTicketsPerDay As Array
Dim intNumOfTicketsPerDay(6)
As Integer
Is there any preference of when one should be used over another?
Transferring A Form Array Into A Private Class Array?
Mar 15, 2010If I make the following array in a push button event and I want to put those array variables in a class array. How do I do that? I am just beginning to learn about classes in vb.net but I am having problems using classes and arrays.Is there any good tutorials on that subject.
[Code]...
Array In One Class Writing To A List In Another Class?
Jun 3, 2011I'm designing a small GUI Windows program that allow staff at a cinema to reserve seats for customers. There will be a total of 60 seats in the cinema. I have two classes in my program:-
1.) MainForm.vb - used for I/O actions and user interaction
2.) SeatManager.vb - used to hold and handle the background methods and functions that make the program work Here is the code for my MainForm.vb class thusfar:-
[Code]...
Forms :: Initialization Of An Array Of A Class Within A Class?
Nov 3, 2011I have main class of Races with mulitple properties. One of those properties has been defined as another class Runners.
So I have a race with multiple runners and when I try to update the data i get an instantiation error.
For the life of me I can't get it to work.
This is what I am trying to do...
In the clsRace class I have defined :
PublicProperty clsRunner(ByVal index AsLong) As clsRunner
Get
[Code].....
Make Class Array Inside Class
Feb 28, 2012I am New to <acronym title="Visual Basic">Vb</acronym>.Net. this is my first test. i try to create small address book. but i don't know what wrong. it compile perfect but when it run it give error and not work. is there any other way to add same class like in class inside array?
[Code]...
What's The Difference Between Variable Array And Object Array
Jan 30, 2011what's the difference between variable array and object array?
View 7 Replies"upgrade" An Object To An Inherited Class, And Keep All The Base Class's Property Values?
Jul 5, 2010bare with me during this silly example. :-) Let's say I have a class like this:
Public Class Animal
Public iLegs as int32 ' Number of legs
Public bWings as Boolean ' Wings? Yes/No
End Class
And another class that inherits the "Animal" class and adds one more property:
Public Class ScaryAnimal
Inherits Animal
Public iScariness as int32 ' 0-100, how scary is it?
End Class
Now, if I have an instance of "Animal" with some values in it, and I decide I want to cast it to a ScaryAnimal for some reason, how do I do that without having to create a new instance of "ScaryAnimal" and copy each property value?Basically I'm looking for a way to do this, without having to write the lines marked with '*** below:
[Code]...
Declaring A Object - Instance Of An Object To Be Created When A Form Loads Or Another Class Is Created
Oct 5, 2009If you want a instance of an object to be created when a form loads or another class is created, you have two options:
Public class example
private IAmAObject As IAmAObject
public sub new()
[CODE]...
Or like this:
public class example
private IAmAObject as new IAmAObject
public sub new()
[CODE]...
I always use the first one. It's more type work but I think it's neater. How about you people and is there any real difference between the two?