I have an Object(Class) that consists of a few List Of(T)'s where T is other classes that can be defined by reading lines of a CSV file.I could (I imagine) do the same thing with XML.My question is when does one choose between the two.Are there cases where one is preferred over the other for data storage?
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i'm working with different classes and different constructors. It's working fine until i try to inherit a class that also has a constructor. vb asks for mybase.new but when i add that vb says that a constructor cannot call itself, when i try it in a different way vb asks the parameters of the constructor of the class that i want to inherit.
View 11 Replies"Create a class called Invoice that a hardware store might use to represent an invoice for an item sold at the store. An Invoice should include four pieces of information as instance variables--a part number (type String), a part description (type String), a quantity of the item being purchased (type Integer) and a price per item (Type Integer). Your class should have a constructor that initialize for each of the four instance variables. Provide a property for each instance variable. If the quantity is not positive it should be set to zero. If the price per item is not positive it should be set to zero."
I attached the code I have. obj is underlined and says "Argument not specified for parameter 'Invoice4' of the 'Public Sub New (Invoice1 As Object, Invoice2 As Object, Invoice3 As Object, Invoice4 As Object)' and so the program won't run. What am I doing wrong?
Public Class Form1
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
Dim obj1 As New Invoice(Val(TextBox1.Text))
TextBox1.Text &= obj1.Invoice1 & vbNewLine
TextBox1.Text &= obj1.Invoice2 & vbNewLine
TextBox1.Text &= obj1.Invoice3 & vbNewLine
TextBox1.Text &= obj1.Invoice4 & vbNewLine
[CODE]...
I am using memorystream to get and store images into sqlserver 2005 table image field. This process is working and I am able to display image in picture box. I need to be able to store PDF files into the same field and be able to display in a picture box.
View 2 RepliesI've managed to make an application at home using a serialport emulator and connector that will read text from a file on my desktop send it to com1 and then my connector program will merge com1 with com2. In short my program works at home but when I connect it to my device it appears the data in DataReceived is a fraction of what my simulator setup at home is producing, which apparently is completely normal according to all these threads I've read here.
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I am coding a program that will allow the user to input 5 payrolls for Store 1, Store 2, and Store 3. The total of the 5 payrolls are then added together and shown in the respective Store's labels. A total label is also there to add up all the totals into one number. The numbers in the label must be in currency form. My problem is the numbers don't add correctly when I hit calculate. The first two numbers add together, but then after that the number just seems to subtract a random amount.
So far I have this --
Public Class Form1
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.Close()
End Sub
[CODE[...
Class1:
Dim v as integer
public sub storeVar(byval s as integer)
v = s
end sub
[code].....
I need to save a reference of variable s in Class2 in variable v in Class1.(i.e. when the value of s changes v also changes (and vice versa)Is this possible since vb.net doesn't have pointers?Will it work if I change "byval" to "byref"?
Ok so here's the story. I have an array of Assemblies which are initiated by [Assembly].LoadFrom() that load a number of DLL's. Upon initialising, a method called InitMain (from the DLL!) is called, which sets a number of variables outside of this method, like here:
Public Class Example
Dim C As Integer = 0
Public Sub InitMain()
C = 50
End Sub
[Code]...
If I call the method Test using that same array of Assemblies somewhere later in the main application (like pressing a button or something to trigger it), it will pop up a messagebox with that says: "C = 0"Why is this? Is it fixable without any odd workarounds?
I must say personally, the WithEvents system is, shall we say, open to extreme false sense of security, so to speak. I like a lot of automation in my code, and tend to provide ways to do things manually, with a "default" behavior encoded. However, as I have just discovered, the withevents doesn't HOOK the event delegate until after creation. So even when you do New MyObject(), if an event is triggered during the Sub New() process, the delegate hasn't been assigned yet, and thus the event (which in my current situation is extremely important) never triggers. which begs the question the point of the WithEvents other than removing "AddHandler" lines from procedural code. Sure it saves on typing, due to code completion, but if that's it, that isn't much of a benefit. One would think that using the WithEvents would allow me to do:
PUblic Sub New()
MyBase.New()
RaiseEvent MyEvent()
End Sub
Tragically, this does NOT work, which royally screws up my lazy loading techniques and other such tricks that were supposed to make my code simpler to use, and instead has made things 10 times more complex, as I have to specifically alter class initialization sequences to be outside of class instantiation. (which should be one in the same, imho).Jaeden "Sifo Dyas" al'Raec Ruiner
"Never Trust a computer. Your brain is smarter than any micro-chip."
PS - Don't mark answers on other people's questions. There are such things as Vacations and Holidays which may reduce timely activity, and until the person asking the question can test your answer, it is not correct just because you think it is. Marking it correct for them often stops other people from even reading the question and possibly providing the real "correct" answer.
I desperately need someones help on this one, as I'm completely stumped where this error comes from.
System.InvalidOperationException was unhandled Message="An error occurred creating the form. See Exception.InnerException for details. The error is: The form referred to itself during construction from a default instance, which led to infinite recursion. Within the Form's constructor refer to the form using 'Me.'" Source="Training Database"
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In my application I have many different forms each use 3 different database. And right now I am placing the connection string in each form but when it is need to change I have to change in every form. Now what I want to store all connection string in a vb class and call them in every form. So that if I need to change I can do in that class. I have stored my connection string in database so even I don't want to connect to database again and again. I have some idea in which maybe a public class is used and some how I will call it on other forms.
View 2 RepliesMy brain is fried at the moment, so here's the scenario.I have a form that adds a member to my VB.NET application.When I press submit I add their details: name and number as well as what products they want (internet and phone). Internet and Phone are their own class as is member.
I want to add that they HAVE whichever they have chosen and with the member store it.
[Code]...
As what happens is once the member is created (stored) I will go to input how much they have used, and then store that. But to do so I will need access to the internet and phone classes, which are associated with said member.
A friend in work suggested the use on classe to store the parameters BEFORE call a method. He's said this is called "Abstract Class". My "know how" of VB.NET is small... so, I want to know of you what mode is the best way: Call a function/sub like that:
[Code]...
I need to iterate through controls using dynamic construction of control names and it looks like this could be what I need, however I never used this before and it does not quite work. What am I doing wrong? GroupBox1 is what I am attempting
Dim x as Integer = 1 For Each ctrl As Control In CallByName(Me, "GroupBox" & CStr(x), CallType.Method).Controls The runtime error is "GroupBox1" not found on Form1 even though I can select Me.GroupBox1 from the dropdown list.
I'm in the process of developing a construction estimating program with vb 2008. Most of the programming I'm able to work myself through, but the problem and question that I have is I would like to incorporate a part of the program where I can import pdf, jpegs, tiffs of blueprints and have the ability to then set the scale, take area and length calculations, and basically do quantity takeoffs.
View 8 RepliesI have created 3 classes which inherits from(System.Collections.Specialized.NameObjectCollectionBase)
The first class "SQLCommandsCollection" stores "SQLCommands" in a collection.
The second class "SQLTableNamesCollection" stores "SQLCommandsCollection" objects in its collection.The Third class "SQLDBNamesCollection" stores "SQLTableNamesCollection" objects in its collection.
Ultimately I will sit with a "SQLDBNamesCollection" collection which contains all Table names and its respective SQLCommand objects.
I would like to store this "SQLDBNamesCollection" object in my.settings("QueryViewerQueriesPerTableNamePerDBName")
at runtime but I am unsure what this settings type should be.
I have tried system.oject but this does not seem to work as I get an "Unable to cast object of type 'System.String' to type 'Fusion.SQLTableNamesCollection'" exception when I try to retrieve from settings. See below code.
[Code]...
How you might construct an array like the following: one column or entry would be a single integer, like 0, 1, 2, 3, 4... - i need this as an index of each one's position in the list the second would be 0 or 1, or true or false the third would itself be a list of integers 0,4,5,2,7,2,5,2...
So all together one entry would be {0; 0; 0,4,5,2,7,2,5,2} while the next might be {1; 0; 6,8,2,5,2,3}
I'm having a terrible time wrapping my head around this. It's mostly the third column which is actually a list in itself, that is giving me trouble
I have two forms. A main form and then another form that you can change settings in. Now when I click on the menu item to get to the settings form I get this error. "An error occurred creating the form. See Exception.InnerException for details. The error is: The form referred to itself during construction from a default instance, which led to infinite recursion. Within the Form's constructor refer to the form using 'Me.'"I've tried these codes.
frmSettings.Show()
Application.Run(frmSettings)
those didn't work so i tried these
dim settings as new form = frmSettings
settings.show()
dim settings as form
[code]....
and those didn't work. I'm using visual studio 2010 Pro.
I want to store additional information about a listview item using a custom class, but I can't seem to get it to work.I'm currently using this code to accomplish something similar using a listbox item.I just want to do the same thing with a listview.
Public Class myListboxItem
Public id As String
Public rootFolder As String[code]....
I forgot to add "Inherits ListViewItem" to my class.I'll update the code listed here to serve as an example for others.
I have loaded a picture in PICTUREBOX1 by this command Me.PictureBox1.Image = Drawing.Image.FromFile("D:C2007BITMAPSpict.jpg")
How to store this picture SQL server 2005 table1's IMAGE column?
I do not want to store image path in table. I want to store picture in image column in any format.
Reason: If I run my project to some other computer that has not images'path stored in database.Then images will be displayed by image field of database.
I want to create the matched strings in vb.net and set them as private, so no one could read them when using ollydby. Here's the
Dim a As string = "ˆ"
Dim b As string = "%"
Dim c As string = "ÿ"
[code].....
My question is How can i create insert,update,delete query by using class file and store procedure. This query is use for 3 tier.
View 2 RepliesI'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.
I know that an interface can contain another interface within it.But;can a class contain another class within it?Can an interface contain another interface within it?
View 9 Repliesstore entire xml document using vb.net in a sql 2005 table
View 5 RepliesI'm selecting multiple files from a FileOpenDialog box. Now I want to store the names in an array. This is what I'm trying to do:
For i = 1 To fileOpenDialogOpen.FileNames.Length
ReDim Preserve fileList(i)
fileList(i) = fileOpenDialogOpen.FileNames(i).ToString()
[code].....
In the application I'm documenting, sometimes a value is stored in a Public variable & other times it's passed to/from a Public Property which does nothing except store it in/retrieve it from a Private variable. (And in one memorable exception, the Public Property stored it in a Public variable-I'm almost certain that was an oversight by the original programmer though.)
I know that passing it to/from the Public Property has the potential for better validation, but if the Property doesn't actually do anything except store/retrieve it is there any benefit to declaring it as a Property? (Or maybe I should put that the other way around. Personally I'd declare them all as properties because that will allow adding validation later-but I'm not rewriting this, I'm just trying to document it and, in this case, trying to figure out why sometimes it's done as a property & sometimes as a Public variable.)
I am attempting to use the System.Management.ManagementObjectSearcher class in VS 2005 (see below) but get a error message for both the ManagementObjectSearcher class and queryObj As ManagementObject - Type ManagementObjectfSearcher is not defined and Type ManagementObject is not defined. how do I use this class in Visual Studio 2005?
Dim searcher As New System.Management.ManagementObjectSearcher( _
"rootCIMV2", _
"SELECT * FROM Win32_ComputerSystemProduct")
[code]....
Does anyone know if you can store VS 2003/2005 code in Team Foundation? If so, is their any configuration needed for Team Foundation?
View 8 RepliesI have a column in the table with datatype xml.
how can i store the entire xml document in that column using vb.net?
