Generic Based On Enum

Sep 2, 2009

I have a generic class Class MyTestClass(Of T)where I know that T will only ever be an enum. Is there any way to declare this restriction to the compiler?And a second question: If the answer to my first question is 'no, there isn't', then what's the best way to cast T to a plain integer? Doing that is difficult when the compiler doesn't know that T is always an enum. [code]That certainly works, but it looks nasty as it apparently involves unnecessarily boxing and then unboxing the enum value. Is there a better way of doing it?

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C# - Get Values From An Enum Into A Generic List?

Nov 21, 2011

I don't know how to convert the following line from VB to C#:

Dim values As New List(Of T)(System.Enum.GetValues(GetType(T)))

My version doesn't work:

List<T> values = new List<T>(System.Enum.GetValues(typeof(T)));

The best overloaded method match for 'System.Collections.Generic.List.List(System.Collections.Generic.IEnumerable)'
has some invalid arguments

The constructor-parameter doesn't take it that way - what cast (or else) am I missing?

For clarification: It is wrapped up within the following generic method

public static void BindToEnum<T>()
{
List<T> values = new List<T>(System.Enum.GetValues(typeof(T)));
//...
}

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Limit A Generic Type Parameter To System.Enum?

Feb 21, 2011

Anyone know a good workaround for the lack of an enum generic constraint?[cod]e...

Is is possible to limit the generic type parameter [I don't know if that's the right name] to an Enum?[code]...

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Enum Value Not Serializing Correctly When Converting A Generic.List(Of CustomClass) To XML

Aug 6, 2010

I have a Generic.List(Of ImportedVehicle) - ImportedVehicle being a simple class as below.There is an enum property which is marked as public.When I serialize to XML using an XMLSerializer, the enum's value is just set to it's default value (which is NotAllocated) and doesn't actually represent the value that is set in code.[code]

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Create A Enum Or Enum Type Functionality Witch Return String (enum Returns Int) In .net

Dec 30, 2009

I have a URL lets say . some time i need to send HTTP and some time i need to send it to HTTPS for that i created a enum:

Private _protocol As Protocol

Enum Protocol
HTTP
HTTPS

[CODE]...

Now when i get value back from protocoltype it returns me integer value as enum do so tell me how to get string from enum or other substitute.

Dim targetUri As String = setting.protocolType & "://www.mysite.com"

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Retrieve Enum Value Based On XmlEnumAttribute Name?

Jun 15, 2010

I need a Generic function to retrieve the name or value of an enum based on the XmlEnumAttribute "Name" property of the enum. For example I have the following enum defined[code]...

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Use Generic Constraints Based On Attributes Rather Than Types?

Aug 28, 2009

I'm trying to write a class that will be in charge of persisting application options. Since the options need to be persisted the values that I'm sent must be serialisable.

Initially I thought I've be able to write a method with a signature like this[code]...

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VS 2005 - Inheriting Class Based On Generic Interface

Nov 17, 2009

I want to define a generic interface which will be implemented by an abstract Generic Class. Basically this generic class is a collection class of any class. Interfaces are in a separate project saved as FileReconciliation. Here are the interface definitions

Interfaces
Imports System.Collections
Public Interface ICollectionCommon(Of T As Class)
Inherits IEnumerable
Function Exists(ByVal oKey As Object) As Boolean
[Code] .....

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Enum Item - Protected Name - Statement Cannot Appear Within An Enum Body

Mar 25, 2011

I'm trying to declare an enumeration and one of the names I'd like to use for an item is not usable apparently. Where I am declaring 'STEP = 3', I get this error message in visual studio: "Statement cannot appear within an Enum body. End of statement expected." Is it possible to use STEP as an item name somehow? [Code]

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ENum Names And Values Don't Match For Same ENum

Jan 2, 2012

RE - FilesystemRights Enum

This Code:

Dim FSRS As Type = GetType(FileSystemRights)
For Each fsr As String In [Enum].GetNames(FSRS)
TextBox1.AppendText(fsr.ToString & vbCrLf)
Next

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Nullable Enum Verse Enum.None?

May 26, 2010

Which is better, using a nullable enum or adding the value None=0 to your enum list?Using nullables requires more code, but I kind of like it since it forces me to think about the possibility. Otherwise I'm liable to forget about the None enum and fail to account for it being a special case.

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Search An Enum Value Inside Of An Enum?

Aug 23, 2011

I've tried the code below but it always returns nothing, It should enter

Protected Function GetTotalDebitAmount(ByRef roEntryDetailRecordBaseList As List(Of PPDEntryDetailRecord)) As String
Dim iTotal As Integer = 0

[Code]....

I need some one who evaluate the part below:

If CBool(Array.IndexOf([Enum].GetValues(GetType(TransactionCodes.Debits)), CInt(oEntryDetailRecord.TransactionCode)) > 0) Then

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Is There A Concept Of "Generic Structure" Similar To Generic Collections, Generic Classes

Dec 16, 2009

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.

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.net - Sort Generic List Based Upon A Different List?

Oct 29, 2010

What would be the fastest way to sort a list that contains a list of objects, based upon another list? An example follows:Say I have multiple lists of employees. Each individual list has a common property value, say "Department". So I have a list of employees, in one list they all have the department string value of "Sales". In another list all the objects have a department value of "Finance". These lists of employees are then contained in a list which holds them all.

I have a second list, which should drives the sort order of the employee lists. The second list simply contains a list of strings like, "Finance", "Sales", "IT" and so on. I'd like my lists of customers to be sorted in the order of "Finance", "Sales", etc.I'm using VB.NET in .NET 2.0

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.net - Can A Generic Version Of A Derived Class Override A Base Method Using The Generic Type

Apr 13, 2012

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.

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.net - Determining A Generic Type At Runtime In Non-Generic Class

Aug 14, 2010

I have a Journal that records entries for different types: Journal(Of ParentT)

[Code]....

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Construct A Generic Interface Class With Generic Functions

Nov 25, 2011

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]

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.net - Creating A Generic List Of A Generic Type

Jun 30, 2011

I 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.

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Generic Cannot Instantiate Instance Of The Generic Type With New?

Feb 8, 2012

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]...

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VS 2008 Accessing Something With A Generic Generic?

Jun 19, 2012

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

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Multithreading - Modify A Generic Invoke Method To A Generic BeginInvoke Method?

Oct 7, 2010

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]....

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Overload Operator In Generic Class With Generic Interface Of Super Class And Inherit Class?

Jan 21, 2010

I can do this without problem.

Class A
End Class
Class B : Inherit A
End Class
Dim Obj1 As A = New B

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How Enum Is Used In .NET

Nov 25, 2009

How does enum work in .NET ?

eg.

Enum eOpenMode
Add = 1
Edit = 2
End Enum

[Code].....

How does this gets compared by their value(1,2) or by its name (add,edit) and what will be memory allocation scheme ?

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How To Use IN In An Enum

Apr 13, 2011

I need to use IN in an EMUN.

-Public enum Talkers
-IN
-GP
-WI
-End Enum

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.net - Can An Interface Contain An ENum

Jan 27, 2010

Can an Interface contain an Enum?I am using asp.net 2.0. Suddenly my code started having problems when I added an enum to the interface below. In it, LookUpType is an enum.

Public Interface ILookup
Property ID() As Int32
Property Text() As String

[code]....

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Asp.net - VB Brackets In Enum?

Mar 24, 2011

I'm finding this in some legacy code and just curious what the brackets are for?

Public Enum myEnum
none = 0
abc = 2

[code]....

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Decreasing Value In C# Or .NET Enum?

Apr 23, 2012

More for interest than actual need.is it possible to have an automatically decreasing enum in C# or VB.NET?

public enum testEnum
{
this = -1,
that,
other,
}

So that that = -2 and other = -3.I'm pretty sure the only way to do it is to specifically assign "that" and "other", but I wondered if there was an automatic way of doing it.

Edit To be clear, I'm simply talking about the automatic assignment of the value, not the actual value of the enum decreasing.

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ENUM As Use It In Other Forms?

May 26, 2009

I'm using vb but still learning it. Here is the question, I have following ENUM created so that i can use it all the form. I created this Enum on my main form (startup form) and want to use in another form.

Enum MyStatus
Good = 1
Bad = 2
Normal = 3
End Enum

Now from other form I'm using it like frmMainmenu.MyStatus.red. I was wondering how i can make it public or create it in a way so that i don't need to give the prefix frmmainmenu before using its value.

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Function For An Enum?

Mar 10, 2009

I have an enum like this:

Public Enum AssociateType
ALL
TIMED
COMMISSIONED
MANAGER
INVALID
End Enum

and I want to get a string based on the value of this enum:

Public Shared Function TypeToString(ByVal Type As AssociateType) As String
'Inputs: An AssociateType of the type of associate.
'Outputs: A string of the type of associate.

[Code]......

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Get Enum Given Its Name (convert From C#)?

Oct 14, 2009

How do I do this C# statement in VB.Net (2005):MainMap.MapType =(MapType)comboBoxMapType.SelectedValue;MainMap only accepts Types so passing the Integer value of the type is not possible. The combo contains a list of strings:comboBoxMapType.DataSource = Enum.GetValues(typeof(MapType));In my case I need to limit the list to less than 100% of the Enum values so code similar to .Datasource= code will not work.So in general I need a way to return an enum given the name of the enum.Maybe I should just do a Collection of Enums (if that is even possible) and use the name as the Key?

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