It seems that my library of extension methods that was written in VB.NET has problems.I have 2 overloaded extension methods Crop().When i reference the lib from a VB.NET project i see them. If reference it from a C# project i can't see them.
View 3 RepliesThe Class Library is an Microsoft Studio extension that generates a file from saving running a custom tool on a template file, following the module from this example I found from Microsoft: [URL]
I can not figure out how I'm gonna debug, build, or deploy this object so I can test it in Microsoft Studio 2010. If you can help me get my class library debugging inside the VSX instance let me know. I will also need to compile and have a delivery method for this extension.
(VS 2008)I'm using a C# library for my VB.NET project. And the method summary/notes or what they are called do not show in intellisense. Is this supposed to be like that? Or is there something I must do to fix it? And if not, will VS 2010 be able to do this?
EDIT: Still unresolved. Now building library dll + xml file, but how to import the xml file in my vb project?
See image: [URL]...
I'm trying to create an overloaded method in a module, but if I type Public Overloads Function GetData(ByVal sql As String) As String it tells me "Inappropriate use of 'Overloads' keyword in a module". Are overloaded methods not allowed in modules?
View 3 RepliesI have had several occasions recently to access a specific class several times over a relatively small time frame.So I've been storing the value of the class in Session and trying to access it on page load, if it's not available creating a new instance and storing that in session.
So instead of constantly replicating the same code for different classes on different pages I'm trying to create an extension method to do this for me.
[Code]...
I'm stuck on what to do when I make my new instance of my class (it would have to have a New() sub)
I'm not sure where to go from here... or even if this is the best way to do it.
Why would I use an extension method instead of just creating non-extension sub or function?
For ex, I could have an extension function called IsNullOrEmptyOrAllSpaces on String, which does a check as its name implies. Or I can write a stand alone function that does the same thing. Other than having the extension show up in Intellisense, is there any advantage? Is a call to the extension quicker/more efficient than a call to a regular function?
In this project I am making a grade calculator; I am modifying an existing code I have to have the following characteristics: I need to modify the DetermineGrade method so that it accepts the maximum number of points that can be earned on both tests (currently, the max number of points is 200: 100 points per test). For an A grade, the student must earn at least 90% of the total number of points. For a B, the student must earn at least 80%. For a C, at least 70%. For a D, at least 60%. If they earn less than 60% of the total points, then grade is F. Here is the exisint code I have for the DetermineGrade method specifically:
Public Sub DetermineGrade()
Dim intTotal As Integer
intTotal = _intScore1 + _intScore2
[code]......
I have an abstract class in vb.net with two subclasses. In the abstract class I have a constuctor that looks like this:[code]I would like to create a second constructor that doesn't take any arguments and just initializes the args to default values.[code]When I attempt to create a new subclass using the second constructor the compiler complains that I'm missing two args to the constructor.Is there a reason I can't overload the constructor in the abstract class?
View 2 RepliesI saw this post and I want to know if this is possible in VB. So like extension method, do extension properties exists in VB.Net? Here I've read they do, but cannot find any examples.
View 3 RepliesWrite an overload for every numeric type or if possible constrain a generic extension method to just numeric types.
View 2 RepliesExtension methods are useful for types that you don't own and can't/don't want to derive from and extend (e.g. reference types and interfaces). Obviously, interfaces should be kept as short and to-the-point as possible, so extension methods for interfaces are particularly useful (e.g. LINQ).For classes, especially classes that you own, they're still useful - but I'm wondering how you determine what should be an extension method or what should be a method in the class itself.Personally, every time I think about it, I keep going round in circles with the following thoughts:If it's useful enough, it should be in the class.It's not part of the core responsibility of the class, it should be an extension method - but if it's useful enough, surely it should be the responsibility of the class...
View 3 RepliesI have a Visual Basic Class Library project. It generates a DLL. Is there a method to generate a static .LIB to which I can do a static link?Alternatively, can I do a static link against a DLL?
View 6 RepliesConsider a MyForm class that contains a shadowed implementation of Show(). It also contains a CreateForm() method, which accepts an instance of the form and calls the shadowed sub:
[Code]....
I know how to add extension method Like (Date.Now.MyExtensionFunction()),But I can NOT find how to add such methods and functions in class (not in module) with vb.net
View 3 RepliesI am trying to write extension methods in VB.NET
Imports System.Runtime.CompilerServices
Module ExtensionMethods
<Extension()> _
[code]....
But I am getting this error.Class 'System.Web.UI.WebControls.ListItem' cannot be indexed because it has no default property
What could be wrong?I am calling the code like this.
ddlSalesmanager.Items.FindByText(survey, StringComparison.CurrentCultureIgnoreCase)
P.S: I ported this wonderful code from C# to VB
I converted some code from c# for a VB.net project I have an object declared as this :
<Serializable()> _
Public Class oUserApplication
Public ApplicationID As Integer = 0
Public ApplicationRoleID As Integer = 0
[code]....
I ran into a strange issue over the weekend while I was working on an asp.net mvc project in vb.net. I created an extension method to convert an integer to the corresponding month it is associated with. I tested the extension method in a console application so I know it is working.
In my asp.net mvc project I have a view and want to call the extension method but I get an error that the extension method is not recognized. I imported the namespace it was contained in and still couldn't shake the error.
Extension Method:
Imports System.Runtime.CompilerServices
Module SiteExtensions
<Extension()> _
[Code].....
I want to implement an extension method in VB.NET that will clone an object of type T.Say, I want
Dim cust1 as New Customer() //...
Dim cust2 as New Customer() //...
cust2 = cust1.Clone()
[code]....
I created a module to add some Extension Methods to a Class. This Class inherits from another parent Class. In the code of my Extension Methods, I would like to refer to the base Class using MyBase. This doesn't seems to be allowed (Error message : "'MyBase' is not valid within a Module.")
[Code]...
I am starting to play with extension methods and i came across with this problem:In the next scenario i get a: "extension method has a type constraint that can never be satisfied"
Public Interface IKeyedObject(Of TKey As IEquatable(Of TKey))
ReadOnly Property InstanceKey() As TKey
End Interface
[Code]...
I'm trying to create an extension method that returns an IEqualityComparer based on a lambda function. Heres the extension method:
<Extension()>
Public Function Comparer(Of T)(Func As Func(Of T, T, Boolean)) As IEqualityComparer(Of T)
Return New GenericComparer(Of T)(Func)
End Function
[Code]...
I have a Direction Enum:
Public Enum Direction
Left
Right
Top
Bottom
End Enum
And Sometimes I need to get the inverse, so it seems nice to write:
SomeDirection.Inverse()
But I can't put a method on an enum! However, I can add an Extension Method (VS2008+) to it.
In VB, Extension Methods must be inside Modules. I really don't like modules that much, and I'm trying to write a (moderately) simple class that I can share in a single file to be plugged into other projects.
Modules can only reside in the file/namespace level so I have one in the bottom of the file now:
Public Class MyClass
'...'
End Class
[Code]....
It works, and "if it ain't broke, don't fix it", but I'd love to know if I'm doing it wrong and there's a better way with less boilerplate. Maybe in .NET 4?
Finally, I know I could write a structure that behaves like an enum, but that seems even more backwards.
I've created a MyFunc extension (in Module Extensions) for all the base types as well as generic arrays, ICollection(Of T) and Dictionary(Of String,T):
Function MyFunc(Of T)(a() As T) As String
Function MyFunc(Of T)(collection As ICollection(Of T)) As String
Function MyFunc(Of T)(dict As Dictionary(Of String,T)) As String
[code].....
how do we access MyBase from an extension method?
i'm trying to extend a Sub called PassDown that would call the form's Base's OnPaint method
<Runtime.CompilerServices.Extension()> Public Sub PassDown(ByVal form_instance As Windows.Forms.Form, ByVal e As EventArgs)
MyBase.OnPaint(e)
but of course, mybase couldn't be accessed this way so is there an alternative?
Can I access values in application settings of web.config in extension method?I have the below code but it is not working:
<Extension()> _
Public Function DocCountExt(ByVal value As Collection) As Integer
Dim maxOffSet As Integer = Integer.Parse(ConfigurationManager.AppSettings(APP_SETTINGS_OFFSET))
return maxOffSet
End Function
The above code does not work.
i want to extend the integer class to a method that increments current integer value by 2. I create a console application and a second module which contains the extension method.
Imports System.Runtime.CompilerServices
Module StringExtensions
<Extension()>
[code]....
and everything works fine. The extension method module can be imported to any other project (Project-->add existing item --> select the vb file that contains the extension method module) and works fine too. But the code is accessible to other users. Is there a method to convert the extension method module to a dll and adding it to other projects as a reference. I tried to do it with creating a class project and pasting the code of the extension method module and compile the dll and then added it as reference to another project and imported the class with the keyword imports, but it didn't work.
I wanna create extension method for IEnumerable(Of FileSystemInfo). However, compiler says "'Sort' is not a member of'System.Collections. Generic. IEnumerable(Of System.IO.FileSystemInfo)". What is strange is that IntelliSense shows this method. Where's error? [code]
View 1 RepliesIn our .aspx pages, we've got lots of this code:<%= CType(GetLocalResourceObject("key"), String)) %>I'd like to add an extension method that I can use in our .aspx views that allows me to do this:<%= GetLocalResourceString("key") %>The code isn't working, though:Imports System.Runtime.CompilerServices
View 1 RepliesI like to create an extension method to Image.FromStream Public Shared Function FromStream(ByVal stream As System.IO.Stream) As System.Drawing.Image
With possibility to cancel processing like Public Shared Function FromStream(ByVal stream As System.IO.Stream, ByVal CloseTask As ManualResetEvent) As System.Drawing.Image
In VB.Net you can easily get the text value of the first child element of an XElement like so:Dim sChildValue = xeParent.<MyChild>.Value()Of course that syntax is not supported in C#, but it produces the same IEnumerable(Of XElement) result as the Elements() method. So we can rewrite the above like so:
Dim sChildValue = xeParent.Elements("MyChild").Value()This Value() extension method is handy because often you are working with small XML documents and you just want the first node that matches. (One thing that annoys me about this method is that it seems to return Nothing/null if the IEnumerable list is empty due to the specified element not being found. To work around this I have created my own ValueOrBlank() method that returns an empty string in that situation instead.)
My problem is that I can't do the same thing in C#:var sChildValue = xeParent.Elements("MyChild").Value(); // won't compile, can't find Value() method
I checked my references/imports and they match the VB.Net project where the same call works. Fortunately I am able to use my custom ValueOrBlank() extension method to accomplish the same thing. But I'm curious as to what's missing in my C# project. I tried right-clicking on the Value() method call in Visual Studio and clicking "Go To Definition" to see if the Object Browser could tell me where the extension method is kept, but it just shows the System.String class. Does that mean this is one of those sneaky VB.Net-only features that the compiler itself supports, like the XML Axis < MyChild > syntax?