VS 2010 The "New" Keyword In Defining A 2D Array Of Objects?
Apr 8, 2012
this is essentially the code in a class module I added to the project.
Module CFKMod
Public Maps(5) as Map
Public Class Map
Public Tiles(7, 7) As Tile
[code]....
The problem is this: NullRefereceException was unhandled - Use the "new" keyword to create an object instance.So I've tried placing the word "new" in various locations in front of references to any picturebox to no avail. I even tried to add this before the ** line:
Maps(1).Tiles(1, 1).pctrbox = New PictureBox
In which case the same error moves up to that new line instead. That seems entirely baffling, because VB is telling me that I need a "new" keyword when it is clearly there. I expect either it is in the wrong spot or I'm declaring something incorrectly.
I feel quite silly asking this, but I couldn't find a definite answer anywhere. in vb.net, how are the array elements defined (if they are defined) for, for example:
Dim myarray(5) as int
does, at this point in time, myarray(3) for example have a defined value? If so, what is it?
I am working on a project right now which requires the program to read names from a text file and add those names to a list box(after the program is launched). After they are added to the list box, the user is suppose to vote on the items in the listbox(each click of the vote button should add a +1 to the counter for that name selected). So far I have been able to bring items from the text file into the list box, but am unable to set up the voting system.
I am trying to create a property and declare it as a dictionary. This property will be updated and called upon throughout my project. I may be complicating the issue but here is what I have...
vb.net Private Shared m_ItemName As Dictionary(Of Integer, String) Public Shared Property ItemName(ByVal Tkey As Integer, Tvalue As String) As Dictionary(Of Integer, String) Get
[code]....
What I wish to do with the dictionary is to keep a record of the amount of items selected, the Key will be the Integer in the dictionary and will be the ID of that item in a database while the String will be the name of the item matched to that ID in the database.The user will be allowed to enter up to no more than 10 items at a time (overkill but necessary for the unknown).I was originally going to use an array statically declared allowing up to 10 items (eg. Private Shared m_ItemName(,) As String = New String(9,9) {})
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
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.
First off let me say that I am essentially new to VB.NET, i.e; still learning. Also, I hope that this is the right place to post this question. In a Project I have a Class module defined as:
Public Class Def Public Id As String Public Meaning As String
I want a custom menu when I right click. Like, you know when you right click on your desktop, and you see a bunch of menus, like properties and whatnot. How do I do that with VB.Net? Also, how to add custom?
I have a tricky piece of code in C# that I need translated to VB.NET. That's not usually a problem, as I can do it by hand or using one of the many conversion websites. However, this particular piece of code uses the Yield keyword; and I don't know how to work around that. [Code]
I'm trying to make the combobox get suggested values from a website using the current keyword they have in the box already. For example if I have O, it will show up values that the website has returned with O. The problem is how can I make it work where whatever I type into the combobox, it will get the values, set the datasource and make it show up. So far I have this:The problem is whenever I type something, I cannot get it to set it to the new datasource without the comboxbox becoming the first value in the data source.
Dim pop As New List(Of String) pop.Add("Koolaid") pop.Add("kIMKY") pop.Add("KoolPaid") ComboBox1.DataSource = New BindingSource(pop, Nothing)
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.
I have BIG trouble trying to understand the decleration and creation of an instance with respect to arrays of objects. Basically I struggle with with this error:
Object reference not set to an instance of an object.
complete the test code I made below, so that I can try to understand it..? Been figthing with this for hours..
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.
This is getting on my nerves. All the examples I keep finding deal with Consoles, all I'm trying to do is put data into an array of objects and output them into a Text box, but I don't know the syntax to do that.Here's my class
Public Class Student Private SID As Integer Private firstName As String
I have two methods in a class for placing and rotating an array of objects(Pieces) on a Board.pieces have a bounding rectangle and a property called center that is the center point of the rectangle(piece).what i want is to rotate all the pieces in clockwise or counterclockwise direction ,depending on the mouse direction,when the mousebutton is down on any of the pieces other than the center piece and the mouse moves.can anyone modify my code below to achieve this or post some new code that does this. using the rotatepiece() method below in a timerevent with a buttondown event to start the timerrotates all the pieces in clockwise or counterclockwise direction.
Shared PosArray(18) As PointF Shared Increment As Double 'place pieces in rows [order 3-4-5-4-3]
I'd like to create an array of objects with events. Where do I need to put the "WithEvents"? Should it be placed in the ReDim line or the next one?I'm trying to use a "global" event, like objects of people that recieve a time-event to get older.
I'm having a problem at the moment developing my application. What i need to do is find out how many modems they are connected to my system and send data to each one in turn. I have the programme working for one modem at the moment.
So I can send data to a modem that i specify, for example a modem on COM port 1. I have functions already that will give me a list of COM ports that I need to open.My problem is that i want to dynamically create a new modem object along side existing modems and store them in a collection.
I've been wasting so much time on this. Basically I want to have a list of objects and I want to call some specific methods of some specific bjects..g.MsgBox(Instances(0).Position(0).ToString)It should alert a number that presents the X position, but it is not working... the box does not even appear and no errors.
I am having a problem with objects and arrays of objects. Basically obj_stored holds how many objects I have stored in my text file, in this case t shirts. line(y) is an array that holds each line that has been read from the text file. I then use this to assign values to my array objects properties. For example I know the first line is the color of the first t shirt, second size, third price etc. Then I know the next line will be the color of a new t shirt. There are 6 t shirts in the file.
Dim t_shirt(5) As Clothing.t_shirt Dim t_shirt_purchased As New Clothing.t_shirt For x = 0 To obj_stored t_shirt(x) = Clothing t_shirt(x).color = line(y) y = y + 1 t_shirt(x).size = line(y) y = y + 1 t_shirt(x).price = line(y) y = y + 1 Next MsgBox (t_shirt(4).size)
My problem is it seems to be resetting these values after it has finished. Im creating the object each time and assigning values to it's properties but when it's finished it all resets and says 'Object reference not set to an instance of an object'. I'm new to OOP and was wondering what sort of approach i would take to doing this, if the one i am taking is wrong.
So I am aiming to: Read everything in from the text file. Create new instances of the objects depending on how many t shirts are stored, (5 t shirts = 5 objects) Assign the values to my objects properties.
Migrating from VB6, a control array of flexgrid objects. Obviously flexgrid is not supported by VB.NET, so DataGridView objects have to be used instead. I tried this alternative to placing them in a list.
I have two DataGridView objects which share a lot of code as well as event handlers. They are named D1 and D2 and many properties, such as column headeders etc., are set at define time. The control array is simulated by passing the "index" and selected grid as parameters in subroutines. For example, the routine to fill the grids, is as follows.
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
I need to declare dozens of objects (Textboxes and Checkboxes mostly) into differents arrays but when i try to do this, they are added as strings and not as objects. I'd like to add them as objects to run through them recursively.
[URl] The code in question is specifically at line 143. Whenever I try to access a label in the array like so Dicelbls(0).Text I get a null reference error. Obviously I am not declaring the array right?
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
