Sorry if the title isn't very clear. This is a VB.NET (2010) question I have a superclass called "Device" which has a number of subclasses that inherit it. Some of those subclasses also have subclasses. In particular, I have a class called "TwinCatIntegerDevice" which inherits "TwinCatDevice" which inherits "Device."The relevant parts of Device look like this:
[Code]...
I am trying to override a property of a subclass of an inherited base class. I've tried to simplify this code as much as possible but am not comfortable enough with my own abilities to simplify anything else without loosing the ability to understand an answer.The property propertyName in the otherClass is currently incorrect. I want to be able to override propertyName in baseClass with the propertyName in otherClass. Is this possible to accomplish?
Public Interface interfaceName
Interface iInterfacePropertyName
Enum enumName
[code].....
Given this example:
Public Class Car
End Class
Public Class Vovlo
Inherits Car
End Class
[Code]...
where Car.CubClass is either a Volvo or BMW if the car object has a subclass, or a car if it do not have a sub class. The problem is how to get the Car.SubClass.
I am working on a parser for a serial data protocol. I have an overarching Packet class, a couple sub-classes such as CommandPacket and StatusPacket, and then a few sub-classes of each of those:
[Code]..
While I don't think it is entirely relelvant to the discussion, I am doing this in VB.NET. There is also a similar (but not quite the same) question posted here: Java - subclass validation design pattern
I have subclassed the ASP.NET Panel control to customise the rendering of the GroupingText. However, while it appears fine in the final output, it is not appearing correctly in the designer. A sample of what I am doing follows: Is there anything else I need to do to make it appear correctly in the designer?
Imports System.Web.UI
Public Class CustomPanel
Inherits Panel
Public Overrides Sub RenderBeginTag(ByVal writer As System.Web.UI.HtmlTextWriter)
Me.AddAttributesToRender(writer)
[Code] .....
switching back to the code causes an error dialog to pop up with the message:"An error was encountered during code generation.The changes you have made in the designer have not been committed to the source code.it is recommended that you close and reopen the source file.The error message follows: Error HRESULT E_FAIL has been returned from a call to a COM component."The source code the Designer
View 2 RepliesI'm developing this Usercontrol and I want it to capture theParentForm 's WM-Messages.I know how to just Subclass a Form, from the Forms code. Like:[code]But how do I do this from the Usercontrol? In VB6 I would have used code like:[code]All I want is to capture messages from the ParentForm's Window.
View 5 RepliesIn VS2010, targeting Framework 4.0, I have a UserControl which contains a TableLayoutPanel with an empty second row.Is it possible to add items to this second row using the Windows Forms Designer, or do I have to do it all via code?
EDIT: In reply to Hans Passant's comment, the linked question references a UserControl being used inside another control.I am asking a question about inherited controls.I have created the following test code, where TestControl is a UserControl containing a TableLayoutPanel named "TableLayoutPanel1":
Imports System.ComponentModel
Imports System.Windows.Forms.Design
<Designer(GetType(testDesigner))>[code]....
creates a control which, when viewed in the designer, contained a TableLayoutPanel named "TableLayoutPanel1" which is not designer-editable.Creating a new UserControl, not inheriting from either of the previous UserControls, and then placing a TestControl into it creates an instance of TestControl with a Designer-editable TableLayoutPanel named "TestControl1.TableLayoutPanelX".Is there any way to make the TestInheritedControl class, shown above, Designer-editable?
we changed the mapping from the table per concrete class to the subclass strategy and now the UnitTests fail, but I cannot recognize why.There's one base class Article and a child one SemifinishedArticle with no specific properties.
Article.hbm.xml:
<?xml version="1.0" encoding="utf-8" ?>
<ibernate-mapping xmlns="urn:nhibernate-mapping-2.2"
[code].....
I'm trying to capture the initial value of a listbox immediately after it's clicked on, and before the SelectedIndex is changed. The following was taken from: MouseDown in WinForm ListBox Kills SelectedIndexChanged, converted to VB. The ListBoxComponent Class is in a Component that shows at the top of the Toolbox.
Public Class ListBoxComponent
Inherits ListBox
Public Const WM_LBUTTONDOWN As Integer = &H201
Public Event PreSelect As EventHandler
[code]....
I have a base class, "B", which has two constructors, one with no paremeters and the other that accepts one param, an integer. I have a subclass, "S", which inherits from "B" and does not define any constructors in it. I create an instance of S, attempting to pass to the constructor an integer.
I get the error: Error 1 Too many arguments to 'Public Sub New()"
This surprises me because I thought that if a constructor is not defined in the subclass, S, that the base class constructor method, specifically, the one with the single integer param would be invoked w/o an error. why I am getting this error? Are constructors a special case?
In re-engineering a windows forms application, I find that a lot of code-behind in the various form classes is duplicative and I'm trying to centralize as many procedures as possible into a base class which can be inherited and used by the subclassed forms.
This process seems to be going well and is making the code in my subclasses much simpler and hopefully easier to maintain, but I'm not sure where to draw the line between leaving code in the subclasses and engineering for generic resusability and moving it to the base class.
Specifically, in some subclasses I have code which manipulates variables and objects specific to the subclass, and although I could move the code-behind into the base class, the base class code references specific objects which are needed to compile. For example, each subclass manipulates a databound datagridview and form detail controls which allows the user to select between multi-record and detailed single-record views of a datatable.
In Visual Basic 2008 do I need to declare dummy data objects in the base class so that the base class will compile? Or is there a way to indicate that the data objects will be provided by the subclass?
take a look at the following code:
[Code]...
I have a copy function that I'd like to override in subclasses to return the type of the subclass. Here are my interfaces:
Public Interface IBase(Of T)
Function Copy() As T
End Interface
[Code]....
How can i do a thing like: Myobject.Properties.Property?
Good Example: The datagridview has the 'Databindings' with an arrow, along with many other properties, How would I do something like that? This is the code I have:
Interface MyProperties
ReadOnly Property [Property]() As String
End Interface[code]....
I get an error 7th Line where it says "Return me", cannot cast FilteringDGV to MyProperties.
I have a superclass NetworkTest and 3 derived classes PingTest, Pop3Test, SMTPTest. I want to create a big list of all the tests, like this:
[Code]...
I have a base class that contains a fairly large number of parameters in it's New constructor. I have 7 subclasses that inherit the Super base class. My question/issue is, all of the subclasses use the same values for most of the parameters in the New constructor of the base class and these subclasses can be called one after the other. I would like to populate the common values for the superclass and then use those for each of the subclasses, but I can't come up with a good way to do this. If I could figure out how to do this, I wouldn't have to pass all of those parameters in the MyBase.New call for each subclass. I'll try to illustrate with some code .
[Code]...
I have 2 business classes, user & salutation and 2 DAL classes of the same name.
The business classes both have properties of the data class E.g.
Public Property Data() As Data.Salutation
Get
Return _Data
[Code].....
To access some data, you would do Business.Salutation.Data.SalutationID
Both busines classes inherit from BaseClass which contains all my database access methods.
Is there a way that I can access the Data property of the inheriting classes from the BaseClass?
I assume I will need to use reflection as the property types will always be different.
I read somewhere that older VB .net (pre VB .NET 2005?) couldn't use overloaded operators in a C# class. Is it true for overloaded cast operators?Either way do you guys think it's a disadvantage for a C# class library not to include them and arithmetic methods as actual methods for other languages, like:
ToDouble
ToFloat
FromDouble
Add
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So Google's not a good choice for looking up examples for overloaded operators like "And" or "Or", because it tries to parse them as operators to the search query itself. MSDN also provides no examples of how to implement an overloaded And operator, so I'm not certain how to properly overload it for my project.Does anyone have an example of "And" at minimum? "Or" or "Xor" (or any others) would be a bonus. I'm not certain if I need to overload these operators in my objects just yet, as I'm still building them out and haven't planned beyond just yet. But having examples around that might get indexed by Google will probably help save the sanity of a lot of people...
View 2 RepliesIn this project I am making a grade calculator; I am modifying an existing code I have to have the following characteristics: I need to modify the DetermineGrade method so that it accepts the maximum number of points that can be earned on both tests (currently, the max number of points is 200: 100 points per test). For an A grade, the student must earn at least 90% of the total number of points. For a B, the student must earn at least 80%. For a C, at least 70%. For a D, at least 60%. If they earn less than 60% of the total points, then grade is F. Here is the exisint code I have for the DetermineGrade method specifically:
Public Sub DetermineGrade()
Dim intTotal As Integer
intTotal = _intScore1 + _intScore2
[code]......
I'm working with a third-party library interfacing to an old database system. There's a method - CallProg that calls a "stored procedure" (for lack of a better translation - any Pick users in the crowd?). However, instead of doing something like this:
Public Sub CallProg(ProgName, ParamArray ProgArgs() As String)
...
End Sub
[code].....
I have two computer. Both have VS2003, but on one of them, Navigate() is overloaded. Its either Navigate(string) or Navigate(string, ref obj, ref obj..and so on). But on my other computer, Navigate only has Navigate(string, ref obj, ref obj....)
View 1 RepliesI have created a dialog as a winform and am calling that winform like this:
Dim dlgEditChangeOrder As New dgEditChangeOrder
Dim dlgResult As DialogResult
dlgResult = dlgEditChangeOrder.ShowDialog
pretty simple. I want to be able to set the visiblility of a control on the win form when the win form is called. I would like to do this as a constructor so I could write the following. Dim dlgEditChangeOrder As New dgEditChangeOrder(visibleIsTrue)
Can someone give me the contructor code to make this happen? The reason I am concerned is I dunno if its legal to do this inside a winform since the winform is loaded bby the precreated IntializeComponent() function
I have some VB6 code that I am converting to VB.net and came across this section
Declare Function TmSendByLen Lib "tmctl.dll" Alias "TmSendByLength"(ByVal id As Integer, ByRef msg As Any, ByVal blen As Integer) As Integer
'snip'
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I have not come across the Alias term before but I can guess what it does. What I am unsure of is the reasoning behind overloading the alias. If that is what is happening.I need to create overloads for the TmSendByLen function as the 'As Any' is not supported in VB.net so I am not sure if I should just remove the alias or if I should leave it in place.
I am looking for a little expert design insight.I am trying to save an overloaded property from a generic class.
Base Class
Public MustInherit Class BaseEvent
Public MustOverride ReadOnly Property IsWorkCalendar() As Boolean[code]....
I tend to loath repetition in code, so when I come across a problem where the only different is types I tend to use generics. Coming from a C++ background I find vb.net's version to be rather frustrating, I know C++ has template specialization and I guess vb.net does notso what I have is a set of routines that do the exact same code regardless of type being passed.something like this
Public Sub decision(Of T)(ByVal a As T, ByVal b As Integer)
If b > 10 then
gt(a)
[code].....
I have an abstract class in vb.net with two subclasses. In the abstract class I have a constuctor that looks like this:[code]I would like to create a second constructor that doesn't take any arguments and just initializes the args to default values.[code]When I attempt to create a new subclass using the second constructor the compiler complains that I'm missing two args to the constructor.Is there a reason I can't overload the constructor in the abstract class?
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Why is the first line not correct? What it wants is a System.Type and a System.String but refuses to work.
As some of you may know i been working on an inventory program, for this part of the app the user enters an ID number and clicks search, the app searches for the ID and shows if it exists or not.
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