Implement IEqualityComparer<T> In Program?
Apr 8, 2009I have the following function that loops through a directory and checks for a specified folder and file[code]...
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Create A Shared IEqualityComparer?
Jan 20, 2012I'm doing some LINQ which requires a custom comparer, so I created a new class implementing IEqualityComparer. However, when I use it, I have to create an instance of it each time.
Dim oldListOnly = oldList.Except(newList, New MyEqualityComparer)
Dim newListOnly = newList.Except(oldList, New MyEqualityComparer)
I may be misunderstanding how .NET works, but it seems wasteful to create a new comparer each time. I really just want one instance (the equivalent of static in C++/C#).So I tried creating a "static" class, which in vb.net is a module. But got an 'Implements' not valid in Modules error.I then tried making the Equals and GetHashCode function shared methods on my class, but got this error: Methods that implement interface members cannot be declared 'Shared'.how to accomplish my goal here?
.net - IEqualityComparer(of Object) For Intersect Or Except Not Working
Jun 15, 2012enter code hereWant to remove items from a Main list , but give an error 'Unable to cast object of type <ExceptIterator>d__99'1['
[Code]...
C# - Use IEqualityComparer<T>.Equals() In ToLookUp<T>() Extension?
Aug 5, 2011I stumbled upon an article regarding the Birthday Paradox and it's implications when overriding the GetHashCode method, I find myself in a bind.In tests, we found that in calls to the ToLookup() Extension, only GetHashcode is used, despite providing the implementation for Equals.
I think I understand why this happens, the internal working of ToLookup, HashSet, Dictionary, etc, use the HashCodes to store and/or index their elements?Is there a way to somehow provide the functionality so that the equality comparison is actual performed using the equals method? Or should I not be concerned with the collisions? I haven't done the maths myself, but according to the first article I linked, you would only need 77,163 elements in a list before reaching a 50% chance of collision.
If I understand this correctly, an Equals() override that compares property by property such as
Return (a.Property1 == b.Property1 && a.Property2 == b.Property2 && ...)
should have a zero chance of collision? So how can I get my ToLookup() to equality compare this way?
In case you need an example of what I mean:
[Code]...
I can get that to work with an override of GetHashcode(), no problems. But I don't want to use GetHashcode because if I have, for example, 109,125 elements in my list, apparently I'm already at 75% chance of collision? If it used aforementioned Equals() override, I think I'd be at 0%?
Custom Generic.IEqualityComparer(Of T) - Compiler Errors
Jun 17, 2009I am trying to implement a simple IEqulityComparer to use with LINQ collections. I have written the following code which is reduced to its simplest form for discussion purposes...
Public Structure bob
Dim SiteID As Integer
Dim fred As String
End Structure
[code]....
The problem that I have is that both functions throw the compiler warning "function 'getHashCode' (or 'Equals') shadows an overridable method in the base class 'Object'. To override the base class method, this method must be declared 'Overrides'."
However, if I declare them as Overrides, I get the error "function 'GetHashCode' cannot be declared Overrides because it does not override a function in the base class."!!I am also getting a compiler error on the "Implements" line to the effect that I must implement "getHashCode" but I presume that is a result of the first problem.
How To Implement Timer In Program
Aug 21, 2009I am trying to implement a timer in my program and i am unable to do so till now.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Static intCount As Integer
intCount = 10
While intCount <> 0
Dim fileReader As String
[Code] .....
How do I implement a timer that will close the IE after every 5 seconds till the count runs out?
Implement A Timer Into Program?
Apr 8, 2012I'm trying to implement a timer into my program, because I want to take a capture from a webcamdevice every x seconds.I've wandered around google all day and tried to implement all kind of timer classes (with system.threading because I can't use system.windows.forms.timer) but I won't figure it out!
View 14 RepliesImplement Dll In Dot Net, Call From C++ Program
Jun 16, 2009I have an existing program, and it uses DLL files to do things I wish to implement a DLL in VB.NET the DLL's are not COM, they are standard call the method or function type DLL's
How would I implement the following in a VB.NET DLL extern "C" void __Export_TYPE HelloWorld(char *path)
Implement IMessageFilter In Program?
Jul 7, 2009I use VB.NET 2005 i need to implemente IMessageFilter for MSWord object.
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Jul 16, 2009I have an interface program written in VB .Net (VS2008xxx.dll). Is it possible to implement the Interface in a VB6 program (VB6xxx.exe)?
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Jan 25, 2010I'm looking to implement a sort function in my program however I am new to VB and don't know how to. Basically I have 6 objects in my program racing across the screen and what I would like is a leaderboard showing the current top 3.
View 13 RepliesImplement An Abstract Event In Program?
Jun 2, 2009I am trying to implement a service object class for the POS for .NET library using VB9. Specifically, the BillDispenser class. I define my class and inherit from Microsoft.PointOfService.BillDispenser. As normal, it creates stubs for all the MustOverride (abstract) properties and methods that I need to override (I love that), EXCEPT for the events. Apparently thare two events defined as abstract (MustOverride) in the POSCommon base class, but VB doesn't generate stubs for them.[code]...
View 8 RepliesImplement Undo In Drawing Program?
May 13, 2009I try to implement undo in drawing program I want to save the bitmap after every drawing and push it to stack then when the user click the button it will change the image to the last bitmap saved in the stack here is my code
Private Sub PictureBox1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseUp
Xend = e.X
Yend = e.Y
[code]....
Implement Very Simple Validation Into A Program?
Mar 30, 2010I'd like to implement some very simple validation into a program I'm writing, but I have no experience in this area, so I'm not sure how to implement it.I'd like one to have one make sure that text entered in to a text box has only regular characters (A-Z, a-z), but I'm not sure how to go about it!
View 3 RepliesImplement Copy, Cut And Paste In Drawing Program?
Feb 28, 2009I want to implement copy, cut and paste in my drawing program (copy part of an image that is selected)I don't know how to start?
View 10 RepliesImplement Drag And Drop Functionality In Program?
Oct 1, 2011I want to implement drag and drop functionality in my program, but it isn't working. Here's the
vb.net
'I removed the code because it wasn't needed anymore ;)
I've set the AllowDrop property to true, and when I drag a file onto a program, the cursor changes to Unavailable, and I can't drop my file.
Implement Printing Functionality Into A Simple Program?
Apr 22, 2010I'm trying to implement printing functionality into a simple program for my company. It's not necessary, but it would be a nice finishing touch for everyone. And really, in practice, my printing feature works. My problem is that each line is printed on a separate page of paper and I can't find a way to just like, print a page.
It doesn't have to be fancy. I know that I won't need word wrap, nor will anyone ever print more than one page. Here's my ginked & modified code thus far:
Private Sub PrintDocument1_PrintPage(ByVal sender As System.Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage
Dim linesPerPage As Single = 0
[Code].....
Implement TCP KeepAlive In Program On A TCP Client(socket)?
Apr 24, 2012I want to implement the TCP KeepAlive in order to check dropped connections by running a timer.
In my case, I have a TCP Client (using socket class) and a third party server (i have no control on it).
How can i use the TCP KeepAlive on my TCP Client in order to check the connection state?[code]...
Implement Port Blocker And Network Monitor In Program?
Jan 4, 2011I want to write a program that can control port communication in a PC by blocking certain port based on the admins request and also monitor incoming and outgoing network traffic. Can i achieve this using vb.net winsock?
View 1 RepliesVS 2005 - Program To Implement Queue Using Circular Array?
Nov 30, 2009I'm a newbie in visual basic. We have a project in our school in implementing queue using circular array.
View 5 RepliesVS 2008 Implement A BGW And Want To Report Progress To A Progress Bar For TextFieldParser Program?
Feb 14, 2012I am trying to implement a BGW and want to report progress to a progress bar for my TextFieldParser program, sometimes if your opening very large files it takes a while and I would like the user to be able to see the progress and have some interaction so they know the program is still running I am a little hung up on what to in the reportprogress
I have:
worker.ReportProgress(0, myReader.ReadFields())
and its not doing anything, I didnt expect it too since ReadFields is an array
parser
Private Sub BackgroundWorker1_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
Dim worker As System.ComponentModel.BackgroundWorker = DirectCast(sender, System.ComponentModel.BackgroundWorker)
[code]....
Implement Registered Program To Accept Registered Key From Keygen?
Dec 8, 2010I have a application that will prompt the user to enter a serial key in after 30 days...and how do I get the application to know the key is valid?Also i would also like to make a keygen that will work with this program.Where I will enter the company name and generate the key from the Name enter.
View 4 RepliesImplement Something In VB?
Mar 14, 2011How to implement such a feature in vb.net??
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Apr 5, 2012We have a vb.net application where we have implemented multithreading. We determined that we need to either implement .net remoting or WCF. After researching remoting in .NET on MSDN, Microsoft considers remoting legacy for .NET framework 4.0 and recommends using WCF instead. My question is: can we implement WCF functionality into our VB.NET application or do we need to rewrite the app from the ground up in WCF?
View 1 RepliesImplement Threading In App?
Sep 1, 2010I have a program that I would like to implement using Threading.I wand to load a form that takes a couple of minutes to open using threading.Here is my code
Imports System.Threading
Public Class frmAdjustments
Function LaunchForm() As Integer[code].....
I am new to .net programming and could use any suggestions you may have. I'm trying to grasp the concept of multithreading apps and would like to have both my main form (Adjustments) and the (frmNewAdjustments) form to load concurrently.Here is the error I receive with the code above: Overload resolution failed because no accessible 'New' can be called with these arguments:
.net - Implement VB With Statement In C#?
Sep 3, 2010How would you create an extension method which enables me to do the following (warning: exteme pseudo-code)...
class FooBar
{
Int32 Foo { get; set; }
String Bar { get; set; }
}
new FooBar().With(fb => new Func<FooBar, Object>(instance =>
[Code]...
C# - How To Implement Of A Generic In .net
Mar 13, 2011This is just a Translation question. But how do you write a the following C# code in vb.net My problem is that i don't know how to rewrite the this part of the generic T. C# code i want to translate
public static void ShouldEqual<T>(this T actualValue, T expectedValue) {Assert.AreEqual(expectedValue, actualValue); }
[Code]...
C# - How To Implement Tracing In .net
Aug 7, 2009I am implementing a tracing mechanism myself. Now what I'd like to know is what is the best way to implement this mechanism(I mean, the architecture).[code]But then I saw there is an TraceListener class that let's me implement Write and WriteLine methods. The big drawback is that both those methods allow only strings as arguments, and I'd want to be able to send a lot more info than strings. What should I do? Maybe my first ideia is the best?I do know there are a lot of tracing mechanisms like PostSharp and so, I'm just doing this for learning purposes!
View 1 RepliesC# - Implement A Bitboard In .NET?
Mar 9, 2012My Questions are: Is is possible to implement a bitboard in vb.net? Tutorial/Reference to do bitboard in VB?
C# answers are acceptable because it's not that hard to translate.
C# - Implement The Equivalent Of SQL IN() Using .net?
Aug 4, 2010In .net (c# or vb) expressions, how would you implement SQL's handy IN() functionality?i.e. value in (1, 2, 4, 7)rather than:
value = 1 or value = 2 or value = 4 or value = 7
There are obviously many ways, I'm looking for the most clean and simple!