I've got a web user control (.ascx) which implements a couple of interfaces I wrote; namely IXMLBoundControl and ISectionOverridingControl.I've written a mini-CMS type application that dynamically loads controls onto the page based on information in a database. When I click a button on a web page (.aspx), I want to look at all the controls on that page, and determine if there is a control which implements the ISectionOverridingControl.
I've got my loop and I'm looping through the controls; that's fine. However I'm not sure what the best way is to determine whether or not the control implements the interface. What I'm doing at the moment (and works) is to try to cast each control into the ISectionOverridingControl and catching InvalidCastException: If I don't get the catch; I consider it's worked. If the exception is thrown then it doesn't implement the interface.
It's working, however, I consider this inefficient (relying on exceptions): surely there's a better way in VB.NET (I've seen an example in C# but it didn't convert to VB) to tell whether an instance of a class implements an interface or not?
I am trying to create a class in VB.NET which inherits a base abstract class and also implements an interface. The interface declares a string property called Description. The base class contains a string property called Description. The main class inherits the base class and implements the interface. The existence of the Description property in the base class fulfills the interface requirements. This works fine in C# but causes issues in VB.NET.
I'm not sure that I'm doing the right thing here..I'm writing a user control that's supposed to be (fairly) generic. It's a bit like a modified email client specifically tailored to some of the internal things we do.
The view is composed of two main pieces, a message list and a viewer. I need this viewer to be interchangeable, so if someone wants a different style of view they can simply handle an event and change a property. My original idea was to just have an INoteViewer, but since I'm adding it to my form I also need to guarantee that this object is a Windows.Forms.Control of some sort.
Should I continue along these lines and maybe raise an ArgumentException if I can't cast it to INoteViewer, or should I go a different direction and create a class that inherits from Windows.Forms.Control?
I need to know if a Type implements an interface. [Code] because the Interface IRule itself is assignable of IRule what raises a MissingMethodExcpetion if i try to create an instance:
UPDATE2: IsAssignableFrom in combination with IsAbstract might be the best way to check if a given type implements an interface and is not the interface itself (what throws a MissingMethodException if you try to create an instance).
If GetType(Rule.IRule).IsAssignableFrom(typeAsm) AndAlso Not typeAsm.IsAbstract Then
I have an interface, for the sake of argument called MyInterface.I Have a Control Class, lets name it "Parent" that implements MyInterface.I have another Control Class that inherits Parent, called "Child".I have a final Control Class lets call it "Container", that accepts dragging the parent onto it.[code]I want to modify this not to only accept Parent, but to accept ANYthing that implements MyInterface. I can't figure out how the heck to get it to work. Even more confusing, if I drag the child onto Container, with the code as it is above(checking to see if a Parent was dropped), GetDataPresent always returns false. I would figure it would work, since Child inherited parent.[code]But it bombs and GetDataPresent returns false whether I dragged a Parent or a Child. I'm being an idiot somewhere..
I use the IsAssignableFrom-method to check if the datasource of a bindingsource-object implements an interface i defined. The check happens inside the property-setter like this:
Private WithEvents _BindingSource As BindingSource ''' <summary> ''' BindingSource containing datasource in which search is executed. ''' </summary> ''' <remarks>Datasource must implement ISearchAndFindable.</remarks> <Description("The BindingSource to search within."), Category("Data")> _ Public Property BindingSource() As BindingSource [Code] .....
I had a look through the documentation on the Wiki, but it seems a bit thin. How do I determine if a type implements a given interface using Cecil? For my particular implementation it is important that I do not actually load the type into the AppDomain.m Here's the code that I have so far:
Dim outputModule As ModuleDefinition = ModuleDefinition.ReadModule(outputFile) For Each assemblyType As TypeDefinition In outputModule.Types
'How to determine if assemblyType implements a specific interface?
When I write the following statement in VB.Net (C# is my normal language), I get an "end of statement expected" referring to the "Implements" statement. <Serializable()> _ <XmlSchemaProvider("EtgSchema")> _ Public Class SerializeableEntity(Of T As {Class, ISerializable, New}) _ Implements IXmlSerializable, ISerializable ... End Class
The C# version that I'm trying to emulate is: [Serializable] [XmlSchemaProvider("MySchema")] public class SerializableEntity<T> : IXmlSerializable, ISerializable where T : class, new() { .... }
I have an interface 'ICRUDable' and a class called ClientAddress which implements the ICRUDable interface.
My understanding of OOP would lead me to believe that if I declare a System.Data.Linq.Table(Of ICRUDable) then I should be able to put ClientAddress's in there.
The code I have tried includes;
Dim dc As New CRMDataContext Dim items = dc.ClientAddresses and
I have an interface class (IUser) which is the interface of class User. Now, i want to put these into an IList but am confused as to how i should declare the IList:Dim userList As IList(Of IUser) = New List(Of IUser) Dim userList As IList(Of User) = New List(Of User) Dim userList As IList(Of IUser) = New List(Of User) Dim userList As IList(Of User) = New List(Of IUser) when instantiating should you always use its implementation; and when using it as a type use its interface?
And when im creating a new user should i use: Dim myUser as IUser = new User?
I'm trying to make a .dll that contains a lot of basic functionality that a program can use. Currently i am trying to use interfaces to make a lot of this functionallity independend of the program using it but i hit a snag. The Basic idea is that a programmer will create his own object using the interface discribed in my .DLL file. Then implements those functions as he likes. He can then instanciate a controller (found in the same DLL) and sends his custom object implementing the interface to that Controller. The controller can then be started and will take over all the work. I do not know what type of object is send to the controller and idealy i want to program it in such a fashion that i shouldn't care as long as the object send implements that interface.In code I am trying to achieve the following: (quite simplyfied)
.Dll: Code: Public Interface MyInterface '<----Decleration of the interfaceFunction GetData() As Integer Function SetData(Data As Integer) end interface
[code]....
this propperly. I know that the second i set the interface adaptor in the Controller VS comes nagging that it can not be converted to a "MyInterface" Class. Obviously i am doing something wrong. I can change the datatype that the controller expects to the "MyController" type but that would completely ruin the whole idea of flexibillity. I am hoping someone sees what i am trying to do and can point out where i made the thinking error.
If a class is serialized and has events fired from it that are handled on a form you get the error "Form1 cannot be serialized" in c# you can use (to work around this):
I need to create unit testing project for my current website. The currentw ebsite si written in VB. All unit testing examples are using interface to create mock object. My current VB class does not implment any interface. Can I add interface and implement it to my current class and functions without affecting or changing codes to any pages in my website that call the functions? For examples my current class is like:
I am working in VB.net and have a Class, Foo, that implements an interface, IBar.I have a List of Foo's, but I need to pass a list of IBar's into a function, but I keep getting casting errors, even when I use DirectCast.My code is [code]MainWorks works, but it would be really annoying and inefficient to have to do that everywhere I want to call this function.
I'm making a custom class that mocks the System.Drawing.Rectangle class because the Rectangle class doesn't have a name property. I need a name property because I am adding all of my rectangles to a collection and I need a little more info stored than just their locale and size. So I changed the _onPaint event but nothing is working out when I run the program?
Public Class Rectanglar : Inherits UserControl Public BackgroundColor As Color = Color.Blue Public Sub New(ByVal name As String, ByVal XY As Point, ByVal Widthy As Integer, ByVal Heighty As Integer)
I know that an interface can contain another interface within it.But;can a class contain another class within it?Can an interface contain another interface within it?
I am working on a plugin architecture and after some reading I have settled on one. The host class will be implemented in C# as well as some of the plugins for that host. The issue I am having is that some of my team uses VB.net. So the question, is it possible to implement a C# (plugin)interface in VB, such that when it is dynamically loaded into the host program it will have the methods required by the interface.
Say I want to know more about a class mshtml.htmlinputelement for example.Say I want to know. What is his parent classes? What interface the class implement? How do I do so through object browser?
Since interface provides 100% abstraction over its members then why we are allowed to define a class inside an interface? We can define class inside interface, even instantiate it and call its members ,why? I am not getting the clear picture over this .Why this is allowed and what can be its implication or benefit.[code]
I have one interface that contains four functions. I have about 20 classes that implement this interface. Throughout each class, I see a lot of duplicate code, for example, there are constants declared at the beginning that are in every class. The method implementations (logic) of the interface are mostly the same.It contains duplicate structures. Is this a case where I can eliminate a lot of duplicate classes by implementing an abstract class instead of an interface. What I am striving for is too be able to put common methods from the abstract class as non-abstract methods and then methods that need their own implementation would be marked over-ridable. Can I put consts and structures in abstract classes? If so, that would eliminate a lot of duplicate code across the classes. Is there anything else I should look out for in the classes as a sign that I probably should be use an abstract class instead of an interface.
I'd like to make sure each of the subclasses has a certain nested class whose actual fields are up to the developer.
Nesting an abstract class inside the base abs. class doesn't seem to do the trick because during actual coding, both the nested abs. class and the nested class in the subclass both are available (show up in intellisense).
Having the base class implement an interface that includes a class doesn't work since interfaces only refer to methods that can be implemented, not classes (meaning implementing the interface requires implements methods, but says nothing about classes in the interface.
understanding difference between an interface and an abstract class which has no function with implementation?which is better abstract cls or interface in term of speed, features..?
I've got an Interface that dictates classes that implement it to use a large amount of properties and a few methods. I've been using this interface for some time and I have a large amount of classes that implement it.
Now, I need the interface to become a MustInherit (abstract) class, because I need to implement a single method that must be the same for every class implementing the interface (I mean the implementation must be the same, hence I cannot use an interface anymore).
Is there a way to do this automatically, perhaps even using third party tools such as resharper (which is C# only I think?) or similar? I get a headache even thinking about the work I need to do to make this change manually[code]....
I am reading a book (ASP.NET 3.5 Enterprise Application Development with Visual Studio 2008: Problem Design Solution, WROX)The source code is written in C#, but I am a VB guy, so I am giving it a try. Somewhere in the 2nd chapter, there is a Linq to Sql file used that is generated by drag&dropping the DB tables from the Database Explorer. Because some tables have the same type of fields, there is an interface generated called IENTBaseEntity. The writer says its a good practice to implement this interface in another partial class (not the designer.vb file!). The reason for this is that when the LinqToSql file is modified (and regenerated) the changes wont be lost.
In C# this solution is easy to do (i think), but in VB.Net I get an error, because the concerning properties in the LinqToSql file do not append the 'Implement IENTBaseEntity.Property' line. When I press [Enter] after the interface implementation line, VS generates other properties like this
Partial Public Class ENTUserAccount Implements IENTBaseEntity '--->This line results in the error
' This is not the way it should be
Public Property InsertDate1() As Date Implements IENTBaseEntity.InsertDate Get End Get
In some DLL, I have an interface defined like this (shortened code):
Public Interface wsIInvoice ''' <summary> ''' Perform plugin specific actions for a given memberhip invoice that is processedin an incasso batch, and return success result.
[Code].....
The DLL implementing the interface has a reference to the one defining it. And the defining DLL is imported.
I'm doing exactly the same thing in another DLL, and there VS does not complain.
