i have assignment which using polymorphism to get answer. Below here is answer from the question.anyone give me a code using polymorphism to get this answer
i= 100, j= 200, k= 300
value for i =100
value for(i+j)/2= 150
value for(i+j+k)/3 =200
I have a function called Modify. It is delcared like so:Public Function Modify(Of SIMType As {New, DAOBase})(ByVal obj As DAOBase) As Boolean
You can see that this function is generic. It takes as a paramer a object that is a DAOBase or subclasses of DAOBase.Inside the modify function there is a call like so:
DAOToGP(obj)This is where the polymorphism comes into play. There are four or so subclasses I have created of DAOBase. I have written a DAOToGP() for each of these types. So in the Modify() function, when it calls the DAOToGP(obj), polymorphism should kick in and it should call the correct implementation of DAOToGP() depending on the type that I pass into Modify().
However, I get the following error:Error 20 Overload resolution failed because no accessible 'DAOToGP' can be called without a narrowing conversion:'Public Shared Function DAOToGP(distributor As Distributors) As Microsoft.Dynamics.GP.Vendor': Argument matching parameter 'distributor' narrows from 'SierraLib.DAOBase' to 'IMS.Distributors'.'Public Shared Function DAOToGP(product As Products) As Microsoft.Dynamics.GP.SalesItem': Argument matching parameter 'product' narrows from 'SierraLib.DAOBase' to 'IMS.Products'. C:Usersdvargo.SIERRAWOWIRESDocumentsVisual Studio 2010ProjectsSIMDev_2SIMIMSDVSIMLibGPGPSIMRunnerRunnersRunnerBase.vb 66 39 IMS
I am kind of at a loss here. I am not sure why it cant figure out which function to call.
Okay this is a bit of a noobish question, but I ran across this today and it somewhat puzzles me WHY it would be this way.
Consider the following structure
Public Class Employee
Implements IPerson
Private _MyManager As Manager
[Code].....
Here is my question: I am wanting to have every person implement the IPerson interface, whether they are an employee, boss, or manager. However, they each have an attribute that refers to their leader (employees have a manager, managers have a boss, etc). Each implementation of their leader could be potentially differnt other than they fact that they implement the IAuthorityFigure interface. I am wanting to have the IPerson interface have a property for the IAuthorityFigure, but it throws a compiler error for me when I implement this b/c the IAuthorityFigure is not the same type as Boss or Manager (even though they implement the interface).
I have a class that has two methods called "Add." One method excepts a FileInfoA object and the other excepts a DirectoryInfoA objectSo in my code, I'm adding FIAs and DIAs to property lists. But, it throws an exception because it's trying to process a FIA as a DIA, which means that the FIA is being added to the group of DIAs.I commented out the adding of DIAs to see if it would work and it did. When the DIA is commented out, the FIAs are filtered properly and the code executes properly.This is how my methods are declared:
VB.NET
''' <summary> ''' Adds a DirectoryInfoA class and adds it to one of the appropriate list. ''' </summary> ''' <param name="di">DirectoryInfo</param> '''
[code]....
I wasn't quite sure how to label this but that should cover it all. I am using Linq to Sql classes to query a SQL Server table. That part is working fine. I'd like to add the records to a listbox and not just text. I can do this and it works. To get it to display something meaningful in the listbox, I have to override the ToString() function.
So, I've taken the base class tblVendor and created a new sub class tblVendorListObject that inherits tblVendor and overrides ToString to return Me.vendorName. I then use a foreach loop to iterate through the records returned by the query. Next, I create a new instance of tblVendorListObject and attempt to assign the current item in the foreach loop to it.
[Code]...
I have a couple of small classes to represent parts in a search filter. If the searched value equals NonValue the filter is supposed to do nothing. This is defined in a Base Class:
Private Class BaseFilter
Protected NonValue As Object
Protected sQueryStringBase As String = "AND {0} {1} {2} "[code]......
When I then create a StringFilter and check for allowed value:
Dim stf As New StringFilter()
stf.CheckNonValue(MyString)
I get a NullReferenceException (NonValue = Nothing) , when I expected the NonValue object to be String.Empty. Is this a bug in my code, or am I trying to achieve polymorphism in a wrong way?
Suppose I have an interface IFoo with implementation classes VideoFoo, AudioFoo, and TextFoo. Suppose further that I cannot modify any of that code. Suppose that I would then like to write a function that acts differently based on the runtime type of IFoo, such as
[Code]...
Then I have to do my "If TypeOf ... Is" again. How can I refactor this to take advantage of the polymorphism of the implementations of IFoo without manually checking the types? (in VB.NET, though my question applies to C# too)
In VB.NET, say I have a function Public Function Foo(ByVal currentShape as Shape) Instead up passing in a Shape object, I pass in a subclass of Shape called Square like such: Dim square As Square = new Square() Foo(square). Do I need to convert my Square object to a Shape object before passing it in? If so, how do I do this?
View 4 RepliesCan you define this :
Class
Object
Inheritance
Polymorphism
Abstraction
And could you make it easy to understand I'm having a hard time to understand those terms.
In a program I am writing (in VB.NET, 2008), I have 2 classes, "Receipt" and "Group", each with similar properties, both implementing a custom interface entitled "IIDUser". In my program, I have a number of lists of "Receipt" and "Group", declared like:Friend receipts as List(Of Receipt)
I have written a few functions that apply equally to managing both lists of receipts and groups, declared like this one:Friend Function getNextAvailableUserLabel(ByRef theList As IList(Of IIDUser), ByVal startLabel As Short) As Short
Then called like this:getNextAvailableUserLabel(receipts, s)
I did all this in an attempt for interface-based polymorphism, as I thought writing 2 identical functions (except for that one would be for lists of receipts while the other for lists of groups) would be bad practice (and waste time). However, I get an "InvalidCastException" during runtime. It is explained, "Unable to cast object of type 'System.Collections.Generic.List`1[Receipt_Sorter_v2.Receipt]' to
[Code]...
I'm trying to create a class for storing data on People with another class to store their Bank Transactions.Ideally, this all be hidden away and leave only simple statments, declarations and functions available to the programmer.[code]I know this is possible as these exist in the Listbox Class though can't figure out how it's done.
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View 1 RepliesAs the title says, I'd like to know how I can get the program name but from an extension OR the "Open With: (program)" information.A kind lad here has advised me on using the registry which contains details of all default applications but I've no idea how I can go ahead of that. I've tried searching and using almost all properties of FileVersionInfo but it doesn't seem to work for me.
Right now, what I'm trying to do is to select a path from OpenFileDialog and use Button1 to launch the executable path. However, at the same moment, I'd like to take down the program used to launch the executable path.
Meaning, if the filename is Index.ppt, I would want to record in a textbox that the Program Name is Microsoft Office Powerpoint instead of the usual Index.ppt.
The only way I think is possible is by retrieving the information from the "Open With: (Program)" row in the Properties panel of the file but there seems to be no way of getting it. So any help possible? (:
EDIT: FileVersionInfo.FileDescription property only works for default programs(e.g.QuickTime Player / Microsoft Office Word) and not any subs for it so that won't work in this case.
I would like to know the vReasons why vb.net 2005 is not recognizing changes when there are no errors. It does not capitalze and tab a new entry. When I try to debug it just goes to the previous debug not the current one.
View 4 RepliesI'm currently writing a football management game (Australian football) and would like to pretty it up a bit. The match engine simulates each player as a small circle, much like the old Championship Manager games. While I'm fine with this style, I'd like to improve the look. I'm just using the simple graphics tools in VB to draw circles and the oval in the background which they play on. They move around using a timer. It just doesn't look very good. The movement isn't smooth and the circles look jaggy and unprofessional. Given that I'd ultimately like to release this product, I want to make it look a lot better.
What are some 2D graphics engines that I should look at? I don't need fancy animations or anything, just some nice smooth movement and nice looking circles. Doesn't seem like I'm asking for much does it? It'd be also nice if I could add in a chrome-like look or something along those lines.
As for the menus and such, well, they are currently just the boring grey VB style. That's fine for now but, as mentioned earlier, I want to release this game at some point. How can I change all of the menus and such so that this doesn't look like a game made in visual basic...basically. I've seen skins before but I'm not really interested in giving my game some generic style. I want to be able to customize all of it for myself. I just don't know how to! Simply fiddling with the colours and fonts of the default VB controls isn't enough.
I did a test deployment of my project to a friends computer and the name it installed in his programs list was the name of the company I used to install VB not the name of the pro
View 3 RepliesI am looking at adding styling to my forms and would like to know if it is possible to have the user select the theme and then apply it to their induvidual account within the program.I am trying to make it have the ablilty to be changed so that if people need text sizes different or bg colors changing the can, but to just them not everyone.
View 4 Repliesi have a vb.net program compiled in windows 7 (32bit) but then when i run it in windows 7 (64bit) the doesnt work and it can't the Microsoft.Jet.4.0; What should I do to run the program?
View 3 Repliesi have a problem in creating my program. i am using vb.net 2005. after i finished some modules in my program, i saved it. and the other day, when I'm going to continue my work, i can't be able to edit it. when i run it, the additional features that i created were not found. but, after running my program, i can see my added features in the form. i don't know what to do, because i am not familiar in vb.net, i am just a beginner using it.
View 11 RepliesHow to zip files(Any files or folder ) in vb.net 2005.
View 8 RepliesAt first glance this might looks repeated-old problem but my problem might differs a little from others
i want to create a desktop program to add images to a database (microsoft access 2003)
but the problem is no matter how i tried i can't do it.i have searched the internet[code]....
I have a program written in VB 2005, the computer used to write the code was running in Windows XP and 32 bit Pentium D. Now, my boss want to buy a new computer to run the program, and he wants the one that comes with Windows 7, 64 bit. Can my program run in the new computer without any problem? Or, is there anything that I need to change for it to run there?
View 12 RepliesWhen I try to make a new workbook from excel it doesn't work and returning the following error[code]...
View 6 Repliesevery time i try to establish a data connection between vb 2010 and sql 2005 i get the following error message QuoteA network-related or instance specific error occurred while establishing a connection to SQL server.the server was not found or was not accessible .verify that the instance name is correct and that SQL server is configured to allow remote connection .(Provider:SQL network interface,error:26
View 6 RepliesI am doing Windows applications in VB.NET 2005. I want to use chart in my project. I already asked this question in this site. But viewers said the solution to use "MSChartControl" (but this is for Visual Studio 2008.).
View 4 RepliesI created a DLL with VB6 which registered OK as it contained DllRegisterServer and DllUnregisterServer - these seemed to have been automatically put in place.I upgraded the source code to VB 2005 and built the DLL but now it will not register itself as the DllRegisterServer and DllUnregisterServer elements have not been created in this new DLL. How can I instruct VB 2005 to include these elements?
View 4 RepliesIs there a way to get the program that is locking a file, in vb 2005?
For instance, when I try to open a file that is already opened by another program, can I get the name of the process/program that has locked this file?
How can i open chm file in VB.net 2005 ?
View 1 Replies