C# - How Is Hash Implemented In .NET
Aug 3, 2010[Code]...
The garbage collector in .NET moves objects, so the object's address is not stable. How is Object's GetHashCode() method implemented?
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INotifyPropertyChanged.PropertyChanged Implemented And Not Implemented; Visual Studio Build Error
Jan 2, 2012I'm seeing a strange build bug a lot. Sometimes after typing some code we receive the following build error.
Class 'clsX' must implement 'Event PropertyChanged(sender As Object, e As PropertyChangedEventArgs)' for interface System.ComponentModel.INotifyPropertyChanged'.
And
'PropertyChanged' cannot implement 'PropertyChanged' because there is no matching event on interface 'System.ComponentModel.INotifyPropertyChanged'.
Those error should never go together! Usually we can just ignore the exception and build the solution but often enough this bug stops our build. (this happens a lot using Edit and Continue which is annoying)Removing the PropertyChanged event and retyping the same code! sometimes fixes this.We're using a code generator that causes this error to surface but just editing some files manually triggers this exception too. This error occur's on multiple machines using various setups.
How Can The UrlNormalizer Be Implemented
Nov 27, 2009I found the line in a program that references UrlNormalizerUtil.UrlNormalizer to validate a url. It calls it from a GeneralPurposeUtilities file which is added to the project properties in references as a .dll file.
My question is: where does this file come from? Is is self coded or from some library? how else can the UrlNormalizer be implemented?
.net - Implemented Interface Needs Casting?
Jan 12, 2011I have an Entity class which Implements IWeightable:
Public Interface IWeightable
Property WeightState As WeightState
End Interface
I have a WeightCalculator class:
Public Class WeightsCalculator
Public Sub New(...)
..
End Sub
Why can I not do wc.Calculate(entities)? I receive:
Unable to cast object of type
'System.Collections.Generic.List1[mynameSpace.Entity]'
to type
'System.Collections.Generic.IList1[myNamespace.IWeightable]'.
If Entity implements IWeightable why is this not possible?
Have Implemented IEquatable Correctly?
Mar 18, 2012I saw the question posed here: Have I implemented Equals()/GetHashCode() correctly? but my c# is not as strong, and I am unfimiliar with IEquatable enough that I would like to see this in VB.NET if possible please.My example code (The class will eventually use INotifyPropertyChanged when I get there):[code]
View 2 RepliesWhy Would Compiler Think An Interface Isn't Implemented When It Is
Apr 9, 2010I've boxed in red. The class displayed here does implement INotifyPropertyChanged, but the VB compiler seems to think that the PropertyChanged event as declared does not match the signature of INotifyPropertyChanged.PropertyChanged.Here I've selected the offending line of code. Between this and the next screenshot I literally just cut and paste the exact same line back into the file (i.e., I hit Ctrl + X followed by Ctrl + V).I have this happen sometimes, particularly with the INotifyPropertyChanged interface in my experience but I have no idea if the problem is limited to that single interface (which would seem bizarre) or not.Let's say I have some code set up like this. There's an interface with a single event. A class implements that interface. It includes the event. [code] Every now and then, when I build my project, the compiler will suddenly start acting like the above code is broken. It will report that the Person class does not implement INotifyPropertyChanged because it doesn't have a PropertyChanged event; or it will say the PropertyChanged event can't implement INotifyPropertyChanged.PropertyChanged because their signatures don't match.This is weird enough as it is, but here's the weirdest part: if I just cut out the line starting with Event PropertyChanged and then paste it back in, the error goes away. The project builds.
View 2 RepliesXML Embedded Expressions Implemented?
Sep 4, 2009Can someone explain the nuts and bolts of what's really going on under the covers?
View 1 Replies.show Method Or Operation Is Not Implemented?
Jul 18, 2012I am programming an ordering site in VB.Net and ASP.Net.I start with the main ordering form and the idea is that the user will select a subject from the drop down list and then click a button to retrieve all modules associated with that subject in a second form (smaller than the main order form).I have created the second form (frm2) and added content to it.In the main form inside the method which represents the button being clicked, I have coded the following:
Dim frm As New frm2()
frm.show()
I then get an error that show has not been declared and so I create a method stub for it.I run the program and when I click on the button I get the following error:'method or operation is not implemented.'This points to the following line in the 2nd form:
Sub show()
Throw New NotImplementedException
End Sub
what I need to put inside this method to make my second form load when the button is clicked?
Private Set In Auto-Implemented Properties
Jun 11, 2009I'm going to resolve this bug as "Postponed" as we won't have time to do it for VS2010, but I'm definitely interested in your feedback going forward.
View 6 RepliesVB10, Auto-Implemented Properties And COM?
Nov 30, 2010I recently finished a class that we're using to tie Access to some WCF Services. Of course this means that the .Net classes (and all of their properties) need to be visible to COM. Given that I'm using VB10 and the Contact class has about 20 properties I went ahead and used auto-implementing properties.Much to my surprise, the properties were not accessible from within VBA in Access. I tried marking the properties as ComVisible (which I didn't have to do in the past with standard properties) and it still didn't work. After changing the auto properties to standard properties everything worked.
Became
Public Property FirstName As String
Get
[code].....
Interface Be Implemented Across An Aggregate/composite Class In .net?
Mar 30, 2010VB.NET .NET 3.5 I have an aggregate class called Package as part of a shipping system. Package contains another class, BoxType . BoxType contains information about the box used to ship the package, such as length, width, etc. of the Box.
Package has a method called GetShippingRates. This method calls a separate helper class, ShipRater, and passes the Package itself as an argument. ShipRater examines the Package as well as the BoxType, and returns a list of possible shipping rates/methods.
What I would like to do is construct an Interface, IRateable, that would be supplied to the helper class ShipRater. So instead of:
[Code]...
However, ShipRater requires information from both the Package and its aggregate, BoxType. If I write an interface IRateable, then how can I use the BoxType properties to implement part of the Interface?
ReadOnly Property ListView In ListViewItem - How Is Implemented
Nov 30, 2009how ListView pointer is stored/removed at ReadOnly Property ListView in ListViewItem? How is it implemented? I know ListViewItems are stored in ListViewItemCollection which has constructor New(owner as ListView) but I dont know how pointer to ListView is add/remove in ReadOnly Property in ListViewItem...
View 1 RepliesVS 2008 IPodServiceLib - Method Or Operation Is Not Implemented?
Jun 23, 2009im messing around with this trying to get into my ipod touch the code i found here and there on the net doesnt quite work..Imports IpodServiceLib
Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[Code]...
VS 2010 Comments On Strategy Pattern Implemented
May 18, 2012a debate has been sparked here about the use of the strategy pattern in my classes.
Basically, I have a 'Shape' object that is an interface 'IShape'. We have 'Circle', 'Rectangle' and 'Elongated' that are the concrete classes that must implement the IShape interface.
[Code]...
VS 2010 Dll That Is Implemented By A Class With A Default Constructor
Dec 27, 2010I have a base class which must be overriden. This base class sits in one dll shared by all. The derived classes will each be in their own dll such that the addition of a new derived class can be done by distributing a new dll. The set of dlls, and therefore the set of derived classes, will be discovered by the main program on startup. That's all pretty straightforward. The problem is that the main program needs to be able to query a database to figure out which type of derived class it needs, then create a class of that type. Naturally, it can't know which types will be available ahead of time because even I don't know that. The program has to be dynamically extensible.The obvious way to do this is to have an interface in the dll that is implemented by a class with a default constructor. The sole purpose of that class would be to return an object of the type (one of the derived types) defined in that dll. The derived types can't really be this class, because they can't have a default constructor since the base class doesn't have a default constructor, and the derived class can't make up the arguments that the base class constructor needs.
So basically, each dll that houses a derived class would also house a simple class that implemented an interface for the sole purpose of creating that particular derived class. The main program would examine the dll to find a class that implemented the interface, and once it found one, it could ask it what type of class it created, or it could ask it to create an instance of that class. It seems like there ought to be an easier way to dynamically add new classes to the project. It seems like the derived class ought to be able to tell the main project what type it was. This could be done, except that the derived class would have to exist before any of its methods could be called unless the methods were shared. Since you can't have a shared method in an interface, the interface itself would make no sense at that point, in which case I would need to discover whether the class in the dll derived from the base class in the second dll, just to figure out whether or not I wanted to create it. That's getting convoluted by now, so I guess I'll leave it there. The basic point is that the base class is known to the main program from a common dll. The number and types of derived classes can't be known at this time, so the program has to be able to discover them dynamically. Each derived class will sit in its own dll (or there could be more than one in a dll), and has to be discovered, and instances created, as needed, by the main program.
Why Is The VBCodeProvider.Parse Method In VS2005 Not Implemented
Mar 17, 2011Why is the VBCodeProvider.Parse method in VS2005 not implemented? Is there an equivalent function?
View 2 Replies.NET Auto-Implemented Properties - Compatibility Between VS2010 And VS2008?
Apr 29, 2011I am working on an ASP.NET project where I use VB.NET within Visual Studio 2010. Some of the other developers on the project are using Visual Studio 2008. We all check our code into single SVN repository. I would like to start using Auto-Implemented Properties within VB.NET ...
Property FirstName as String
instead of ...
Private FirstName as String
[code].....
My concern is that this could mess up things for those using VS2008. What would happen if someone using VS2008 needed to modify my class that made use of Auto-Implemented Properties? I am assuming that since everything compiles down to IL code then there would be no issue in binary compatibility. Though a problem would arise when editing source.
Event Based Async Pattern - Correctly Implemented?
Oct 9, 2009I've implemented the Event Based Async Pattern for the first time in a relatively complex class. I'm having some doubts about if I've done it as it should be done, and if there are no better approaches. One of the things that make me frown the most is how I'm currently handling all the cross thread events. This class contains a decent amount of events, about 20. What I've done is created a dictionary in which I have a list of callbacks, one for each event. The keys are a value of an enum containing all keys I created. In the underneath line, eventDelegates is the dictionary, and delegates is the enum.
[Code]....
IDE :: VS2010: Enable Or Disable Auto-Implemented Properties?
Nov 10, 2011I have somehow managed to disable auto-implemented properties in my VS2010 IDE how to turn it back on. Almost every article on the internet loves to explain auto-implemented properties but doesnt give you the crucial option of how to turn it on or off.
View 2 RepliesTabsize In A TextBox Or RichTextBox : Why Microsoft Have Not Implemented It As A PROPERTY
Jun 3, 2010Tabsize in a TextBox or RichTextBox. Anyone know why Microsoft have not implemented it as a PROPERTY?
View 1 RepliesDoubleClick Event Not Firing When DragDrop Code Implemented (ListView)?
Aug 29, 2008As the subject describes, once I implemented support for DragDrop - The DoubleClick event of the ListView control no longer fires.An overview of the code is as follows:
Private Sub ListView_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles ListView.MouseMove
[code]......
.net - Why Can't Access The Backing Field On An Auto Implemented Property From Within An Inherited Class
Dec 20, 2011I have a class that exposes an auto implemented property Enabled
[Code]...
But If I had not use an auto implemented property and declared my own backing-field as follows this is accessible from the subclass: Private _Enabled as Boolean ---- EDIT ----
The abve line is incorrect - this is not possible, it was in fact Protected in the original code which allowed access from the sub class See @JonSkeet answer ---- EDIT Of course I can just access Enabled from the sub class to work around this but can someone explain why this is the behaviour?
Getting A Different Hash Value?
Nov 16, 2011I am at a bit of a loss at the moment. What I am basically writing is the password elements of a membership system. What I do is generate a random salt value, take the registered password, combine the two and then pass the new string through a function which will generate a SHAManaged 512 hash.
I then convert the hash and salt string into Byte arrays and store these in my database.The problem comes when I then compare a login attempt against the original value I am being supplied with a completely different hash for the password being presented by the user, even though it should be exactly the same.
Here is my code when someone registers their new account:
[Code]...
Calculate A MD5 Hash?
Dec 1, 2010I have an openfiledialog, I show the dialog and the user selects there file. How could I calculate the MD5 hash of the OFD.filename/file opened? Or calculate the SHA1, what ever is easiest.
PS: This is in Visual basic 2010 Express.
MD5 Hash Of Images?
Nov 7, 2010I know MD5 hashes have been asked about 1000+ times, but this question is slightly different.I am looking to find the true MD5 hash of an image, but without using a string for the file's location. I am looking to be able to call on the image inside of a picturebox rather than somewhere on my computer or the internet.
For example, I want to find the MD5 hash of an image inside of my picturebox.
If this doesn't make sense, please ask any questions you may have.
Add Hash And Salt To Project?
Dec 26, 2010im creating a simple login / registrate form in visual studio 2008 anplant Hash and salt to my login and registrate forms, im using mysql to connect to a online mysql serverthis is my codes i ahve now
Form 1 - Login
Try
DB_Connect = New MySqlConnection()
[code].....
i really need this working, all works but nothing is encrypted
Anchor - If Statement Using The Value Of Hash In URL?
Feb 6, 2012I have a page with a URL that includes a hash value (www.mysite.com/#123).What I want to do is use that value to determine what is displayed on the page - much like using a querystring.I am using the hash value because the content on the page can be changed client side (I am avoiding page reloads where possible) - if the user then links to another page and uses the back button to return, I need to use the hash value to display the page as it was when they left it.So I'm looking for an if statement that will look something like this:
[code]...
C# - Getting Hash Of A List Of Strings?
Mar 21, 2009I would like to write a function GetHashCodeOfList() which returns a hashcode of a list of strings regardless of order. Given 2 lists with the same strings should return the same hashcode.
ArrayList list1 = new ArrayList()
list1.Add("String1");
list1.Add("String2");
[Code].....
I can first sort the list, then combine the sorted list into 1 long string and then call GetHashCode(). However sorting is a slow operation. I can get the hash of each individual string (by calling string.GetHashCode()) in the list, then multiplying all hashes and calling Mod UInt32.MaxValue. For Example: "String1".GetHashCode() * "String2".GetHashCode * ... MOD UInt32.MaxValue. But this results in a number overflow.
Compare Two Hash Values?
Aug 10, 2009I'm trying to figure out a way to compare two "salted-hash" strings. How can I do this? I know that the salt is a random generated value that's appended to the plain text, then we just compute the hash of that new string.So how can I compare these two values? O_O (The new hash that the user hash written in a textbox and the hash stored in a database)
View 9 RepliesConvert VB Generate Hash To PHP
Apr 10, 2012I have a function in VB.net that returns a password hash. I need to make a web interface to the same database and I'm not sure how to return the same hash in PHP. Does anyone know both languages enough to convert this to PHP?
Code:
Public Function GenerateHash(ByVal SourceText As String) As String
'Create an encoding object to ensure the encoding standard for the source text
Dim Ue As New UnicodeEncoding()
[Code].....