In VB.NET when i define a subroutine (or function) , while declaring arguments , a list comes out. Having values ByVal,ByRef,Of,Optional, and ParamArray. Of these five lists , four are better understood except "Of". I searched and found that "Of" is used for Generics .Generic Class or Generic Method.
But i did'nt find any procedure that how to create and use Generic Method in VB.NET. I found same in VB.C# language.
I have created a Interface and a couple classes that implement this Interface. I am in the process of developing a Shared Class that utilizes the functions that each of the individual classes have, due to the interface implementation.What i need to know is how do i develop this Shared Class so that way each of the methods within it are restricted to a single data type. This single data type needs to be restricted to any class that has implemented the Interface.
Some examples:
Public Interface IVector(Of T)
Sub Add(ByVal v2 as T)
[code]....
As you can see it would allow me to develop one form, since i have standardized the required Subs/Functions for any class the implements the IVector interface. As i am still in developement, i was wondering if my current understanding of the method generics is correct in its current form or what i would have to do to make the Generic Shared Class work in the fashion that i am looking for in the example implementation.
I have defined a Sub in vb.net, with 'Of' type parameter like this:
[Code]...
I want to just add number1 and number2, But as you can see error has occured where i want to sum number1 and number2 saying that '+' is not defined for type 'VarType'. how to add these variables in Such Methods.
We have migrated our Vb6 application to VB.NET using a third party tool. Now we are in a process of Refactoring and introducing object oriented concepts in the application.
In VB6, we were using structures in many places. As a part of introducing object oriented programming,
1. is it a good idea of changing all Structures to Classes? or Is there a concept of "Generic Structure" similar to Generic collections, Generic classes?
2. Can some one guide me any source containing guide lines or best practices for applications that are migrated to VB.NET from VB6 and implementing object oriented programmaing.
This is the original code in c#
public class CategoryRepository: RepositoryBase<Category>, ICategoryRepository
{
public CategoryRepository(IDatabaseFactory databaseFactory)
: base(databaseFactory)
[Code]...
Does anyone has an idea what i should change to let it work and let my UserRepository use the methods in RepositoryBase while implementing the IUserRepository?
I am working with a vb program, but there is something strange on one of my .vb code pagewhen i put the "dot" afther the object name its dont show the methods availables for this objectbut on other vb code pages i can see it. but in this one no.for exmaplethis is a piece of code: Dim sb As New StringBuilder()
View 3 RepliesI am not sure how clear my question is by the title, but I am trying to make Class methods instead of Instance methods in Visual Basic that way I don't have to waste memory and code creating temporary objects to execute methods that don't need instance variables.
I am not sure if you can do that in VB but I know you can in Objective-C by using either a "+" or "-" sign in front of the method declaration. And in C++ (at least I think, I can't remember) you put the static keyword or const keyword in front of the function.How would I do this in VB if it is possible? Or should I just make a separate set of functions that are not members of a class?
Consider:
Public MustInherit Class Column
Public ReadOnly Property ReturnSomethingUseful() As Object
Get
'return something useful
[code]....
But this gives the following error:
Public Overrides Function ParseValue(sValue As String) As Boolean'
cannot override 'Public Overridable Function ParseValue(sValue As String) As Object'
because they differ by their return types.
I accept that you can't do this, but I'd like to be able to preserve the semantics of what I'm. trying to do, which is to have an untyped version that deals with Object, but a typed version in derived classes that knows about the specific type T.
I have a Journal that records entries for different types: Journal(Of ParentT)
[Code]....
I am trying to construct a generic interface class with generic functions. My goal was to use this to implement multiple worker classes for database interaction that have the same basic functionality. Each class will deal with different object for example, category, product or supplier but unless the the functions in the interface are generic that this won't work.This is the interface code that I have but I don't know if I have done it correctly. [code]
View 2 RepliesI am trying to create a list of a generic type in vb.net 2.0 framework.
This is the generic type definition:
Public Class GenericParamMap(Of T)
Public Sub New(ByVal pParamName As String, ByVal pPropValue As T)
mParamName = pParamName
[Code]....
The compiler does not allow a "T" in the method's parameter because it's not defined, but I'm not sure how or where to define it. I thought it was okay to have a generic method definition.
I am trying to write a generic method, to avoid code duplication, which will create or activate a Form as an MDI children, based on its type. But I have to lines in error (see comments).
[Code]...
If i have an object that implements an interface (and don't know the exact object) i can call a sub (DoSomething) by going:
vb
Dim iObj = trycast(something, iInterface)
if iObj isnot nothing then
iObj.DoSomething()
end if
How can I do this for a Generic? such as...
vb
Public Class TestClass(of T)
Public sub DoSomething()
....
end class
I have been using a pretty slick generic invoke method for UI updating from background threads. I forget where I copied it from (converted it to VB.NET from C#), but here it is: Public Sub InvokeControl(Of T As Control)(ByVal Control As t, ByVal Action As Action(Of t))
[Code]....
Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim someproc As Process
[Code]...
I can do this without problem.
Class A
End Class
Class B : Inherit A
End Class
Dim Obj1 As A = New B
I'm kind of confuse on how to use get and set in vb how would i access the get/set method within the class and when i instantiate the class somewhere else? in java i would make a 2 methods call like get_item set_item and i can just use the the method name i made. to retrieve or set within the class/object or when i instantiate it somewhere else. but in vb there is a property method and 2 methods inside(set,get)?
[Code]...
I'm trying to use PGK.Extensions in a T4 template in VS2008 for VB.NET and I get:
RemoveAllSpecialCharacters is not a member of string..
My T4 headers:
<#@ template language="VB" hostspecific="false" debug="true" inherits="Microsoft.VisualStudio.TextTemplating.VSHost.ModelingTextTransformation" #>
<#@ output extension="vb" #>
<#@ assembly name="PGK.Extensions.dll" #> // the dll is found
<#@ import namespace="StringExtensions" #> //Try with and without namespace
[Code]...
I have two methods on the page. One AddMessageToInboxOutbox(params[]) and other one SendNewMessageMail(params[]).
Once user sends an message to other other first message is added to DB and then sent to recipient's email. Sometimes SMTP is heavy loaded and it takes up to 5 seconds to get answer from it. I want to enclose SendNewMessageMail(params[]) with async call using other thread or something. I have never done that.
How do i perform this action right in ASP.NET?
I've seen extended .NET method libraries such as this and this.In VB.NET, since you create your extended methods in a Module, How do I make them into a DLL?? (like in those links above) Its not possible to build and get the DLL from a Module.
View 7 RepliesI created a couple of extended methods in a VB.NET module. I put them inside a Class, built it and got the DLL. From another program I made a reference to that DLL and imported it using Imports as well.The extended methods appear in IntelliSense and it works but a warning appears in the Error console saying,Could not resolve this reference. Could not locate the assembly "nK0deExtendedMethods". Check to make sure the assembly exists on disk. why this error occurs even though I have referenced the DLL?
This is the Class where I've put my module with the extended method.
Imports System.Runtime.CompilerServices
Imports System.Drawing
Namespace nK0deExtendedMethods
[code]....
And I'm having another doubt. In the Imports statement, I have to mention the DLL's name along with the Namespace name. Like this,
Imports ExtendedMethods.nK0deExtendedMethods
Normally you only have to import the Namespace's name, right?
Is that posible to get all the methods name that handle by a Load event? I want to get Form1_Load from eventInfo.
Dim form As Form = Form1
Dim eventInfo As EventInfo = form.GetType.GetEvent("Load")
form.GetType.GetMethod("Form1_Load", BindingFlags.NonPublic Or
[code]......
I would like to know how to use the graphic methods:
-DrawString
-DrawLine
-FillRectangle
I am meant to use these in a method called Drawgraph in order to draw a grid and bar chart. How can I go about this? What parameters do I need to send? What variables do I need to declare?
Take a look at the code below. Here I create a thread, set its name, and start it:
Private Sub fileCreated(sender As Object, e As FileSystemEventArgs)
Dim processFileThread As Thread = New Thread(AddressOf fileCreatedHelper)
processFileThread.Name = e.FullPath
processFileThread.Start()
End Sub
This is the sub that is the thread: Private Sub fileCreatedHelper()
[Code]...
I have a vb.net program that opens and populates several excel workbooks with charts. I need to set some chart options. So far, I have:
[Code]...
I would like to know your opinion on extension methods. Sure, it is a nice feature and makes you feel powerful. It's great to see your own method pop up when typing in a object. But it doesn't really add something new... You can get the job done with normal methods as well. I think extension methods do not belong in object oriented programming. It makes your code easier to read but harder to understand for someone else.
View 2 RepliesI am having trouble doing something that is probably pretty simple!I have a stock listing that is done by 1) a simple form with parameters (Index) and 2) an ajax called partial view that displays the list of stock (based on the params).On this same simple form (Index) I have an action link to an "Add Stock" method which calls another form for adding stock.When the user has finished adding the stock I redirect them back to the stock list page (Index).
My issue is that I would like to "remember" the parameters that were initially entered in this form so the user isn't just directed back to a page with blank parameters forcing them to enter them again.I thought I could simply overload the Index method as such:
[Code]...
I get this error: The current request for action 'Index' on controller type 'StockController' is ambiguous between the following action methods:.Now I have read this post and it's answer but I cannot figure out how to implement the solution. Is this solution applicable in my situation? Is there a better way to acheive what I'm trying to do?
So I created this thread: Invoking Private / Protected Methods Via Reflection From The Same Object Instance (or Base) And we got the problem fixed save for private methods. As this may not be the same issue I thought it may be best to post a different question with the full source. It is still a work in progress but it is functional.
[Code]...
So this class is being inherited by a (so far) empty child class and ProcessStage is being called. Notice that ConfirmFormDataIsValid() sub is private. If you run this it will not find this method. If I change it to protected however it works fine.
CODE:
View 2 Repliesmy question is simple. How do i add methods to the standard DataGridView control of VB.NET
I want to add some methods of my own to the class, but i tried inheritance and i get errors. What are the techniques out there to extend native classes in vb net