I need to create an array of a class type. Populate the values in the class and then pass the array to a subroutine. I havent figured out how to do this properly as I get a null reference exception. Can someone show me how to create/instantiate the array of objects? Here is a simple example with only one property named "_momentum". My actuall class has about 10 properties/variables in actuality
How can I make an array of objects in VB.net. Here is the requirement. Basically I have a class named hotel. I need to dynamically add customers to the hotel class using the Customer class. So basically if in the Hotel class I can have an array of Customer objects that would be great. How can I do this in VB .net ?
Public Class Hotel ' I need an array of Customer objects. objCustomers End Class
Friend Class CellValue Public CellColor As Color = Color.White Public CellShape As Shape = Shape.Blank Public CellName As String = "" End Class
Then in my main I make an array of CellValue but I want to know if the values are also being passed down with the array.
Dim Plan(SizeW - 1, SizeH - 1) As CellValue Dim CellW As Integer = PictureBox1.Width \ SizeW Dim CellH As Integer = PictureBox1.Height \ SizeH
[Code].....
Are CellName, CellShape and CellColor being tied to each element in the array?. The reason is because I need to use these properties to tie certain functions to them. The CellName should have a MachineID which I would have to use to pull some info from a Database.
The Array should also be serialized and deserialized to XML as customer needs to create/edit and delete certain values in the array. And in order to save the array has to be in XML
So the Questions are does it save the CellName, CellShape and CellColor for each element, will it be affected if I serialize and deserialize using XML. If possible, how can I call up the Cellname p.e for a specific array element.
I am creating a game which include guns and bullets and I created everything. I want to have a shorter code which I am going to create a array of objects which are the bullets. Can someone help me? In VB6 it's possible to create an array of objects but I am having a hard time for VB 2008.
I'm writing a ray tracing program that uses snell's law to trace rays through a system of lenses to examine abberations in a given design.I have a class called lens, which holds variables for example, name of the lens, description, number of elements.I want to be able to have a sub class or array within lens (or some other way to manage this data).I wont know what number of elements is until run time.
So I would need to define the array at run time.Part of the idea of my program is randomly generate lens elements within given rules (as in a massive lot), keep the top designs and continually refine them by making billions of micro adjustments to the variables that define the lens etc, which I can pick up later on as it'll save the database/variables.For example, say Lens(63).NumberOfElements = 6.
I want to be able to access Lens(63).Element(3).Radius1 Etc, there will be a bunch of variables under Element, such as Radius1, Radius2, refractive index, horizontal diameter, vertical diameter, and spacing between the next element if it isnt the first.
And Lens(70) may only have 4 elements etc. How can I define a different array size like that in the class under different parent array indexes at run time?
I want to create a user defined data structure, which will be a 2 dimensional array such that each individual square of this 2-dimensional array will also store the score and the grades. ( Iam using VB.NET) More details:
for example: There is an 2 dimensional array with 3 columns and 2 rows, I want to fill each of the
(0,0);(0,1);(0,2) with their own score (Integer type) and grades (String Type).
And this is same for the rest of the squares i.e. (1,0);(1,1);(1,2) and (2,0);(2,1);(2,2)
After creating such custom data structure: "CustomArray", I should be able to create the instance of this custom data structure (which will be a class) and code something like this:
Dim objCustomArray as CustomArray objCustomArray = New CustomArray for i as Integer =0 to 3
I want to create a custom class that has inside an array of another custom class (see my code below) but when the programm runs is crashes. Why? What is the right expression???? Plz help I'm a newbie in VB.net.....
Public Class ctrarray Public nameclass As String Public ctrlindex(glvar_spaces) As ctrlindexclass End Class
I've a treeview in my project form which look like this.
-Cover Page -Video1 -Podcast1[code].....
The user will be able to upload their pages to the respective pages nodes and I am suppose to make it in such a way that after the user uploaded the cover page which is showing at the PictureBox1 which I've use to display the image, and when he uploads the second page image at the PictureBox1, the Cover page image that he uploaded earlier on will not be overwrite.
I was told to create class and use array to store the contain in the respective nodes but I do not have any idea how to do it.
Base class has one field to hold numeric balance value. With 2 methods that accept arguments for adding and subtracting the new input calculating new balance. Sub class has four fields dates, transaction, memo and amount.I have a deposit form, and withdraw form. Each time one transaction is entered it creates an object with sub class fields, then adds to the account collection. My problem is not understanding how to call the deposit/withdraw method and pass the current transaction amount back to the base class to alculate the new balance. Does anyone have any links to information/tutorials on how to perform something like this? As you can see with my code I have tried various different approaches without any success.
If 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]
I've come up with the following and it's partly working.
Public serial1, serial2, serial3, serial4, serial5 As SerialPort Public serialports() As Object = New Object() {serial1, serial2, serial3, serial4, serial5} dComPort = "COM4"[code]....
The above code works fine! But im having trouble trying to now retreive whats stored in the array.In the above example, an entry will be stored in serialports(4), all other array elements will be blank.If I do this it works.
MsgBox(serialports(4).PortName) ' this retuns the value COM4
But I'd like to loop though all array elements and print out ALL the PortNames, The below code doesnt work, I get an error Object variable or With block variable not set.
For i = 0 To serialports.Length - 1 MsgBox(serialports(i).portname) Next
[code]The reason that this is a problem is that this is a collection of EventBase objects, but I'm trying to populate it with child classes instead. For example, I might have a JumpEvent class that inherits EventBase, and this is being put into the EventBaseCollection. That means that value.GetType() returns the type of JumpEvent, which as you might guess does not equal the type of EventBase.The goal of course is to simply loop through all of the various events without having to know anything about the sub-classes. Is there a way to determine the type of the base class so that the OnValidate call will work? Or is this just the wrong way to go about it altogether?
I have a nested class, let's call it class1 and it has class2 inside it; VB.Net eg:[code]
1) How can I define X number of Class2 objects[let's call it: Node(x) array]** with NEW() subroutine called?' this raises error: dim cls2(n) as new class2 end sub.
2) How can I return actual number of Node() array? [code]Outside my class in main project I define cls1 object:[code]Now an array of class2 is created inside cls1.
3) Now,How can I access All of them[node(x) array which is created inside cls1] with all properties and methods available?
I remember I wrote a ProcessManager class with this functionality in .net 2003, nearly 4 years age, I don't have the code now.
I need two seperate lists, which every item is Integer, String, Bitmap - and one which every item is Integer, String String. However I don't know how to do this, or even where to look - I've googled for custom objects and custom object lists. What I'm trying to do is this.Custom Object1 is Integer, String, Bitmap Custom Object2 is Integer, String, String
In one thread I'll be adding items to List1(Of Object1), and processing them, and adding the results to List2(Of Object2), however I need to be able from other threads to look at the list and say only give me the items where Integer = (my thread ID), is this possible? Any help, or even links to information that would be relevant to this request would be helpful?
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]
when using variables in object names.I have a Public class which is called "Tank".In that class, there is a public property called "direction" of an integer type.I keep getting the error:
"Tank is a type and cannot be used as an expression"What I'm doing wrong here ?
Public Class mainroutines() Create Instances of tank Private Tank1 As New Tank()[code]....
I'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
when i do a count it display a list of 25 items in the folderlist.Now i have a main class when i tried to use the following method
Dim MainClass as New ClassB
Console.writeline(MainClass.FolderList.count()) the value reflects as 0 items meaning is empty.i need to retrieve the arraylist from Class B using the MainClass to retrieve those items inside the arraylist.
I'm having problems doing a sort of a custom collection. The collection is Device Classes which is a collection of Device Class. My sort does not produce an error but the treeview control shows nothing. I am not sure what I am missing. I'm guessing just a simple sort won't work here but I don't know what I'm missing in my code. Here's the code that creates the collection
[Code]...
Simply sorting the treeview will not work because it throws off the display of related info for a given device in listview controls. The collection itself needs to be sorted before the data is added to the treeview.
ok first off my over all goal is to create a simple database program. I need to have an index file that i can search and then load the item data from a path refferenced from the index file. So i was thinking that if I have a IndexClass object, that has the following varribles: name as string, Desc as sting, and ImagePath as String.