I happened to have seen some code where this guy passed a lambda expression to a ArrayList.Sort(IComparer here) or a IEnumerable.SequenceEqual(IEnumerable list, IEqualityComparer here) where an IComparer or an IEqualityComparer was expected. I can't be sure if I saw it though, or I am just dreaming. And I can't seem to find an extension...
Before you start pointing me to duplicates just know that I have read nearly all the posts on SO about extension methods. I am just trying to play devil's advocate for a minute to consider the alternative to my working opinion. Recently I was working on a project and a need came up for a method to be a base of an interface. So I suggest...
I got an really bad idea :) When exploring extension methods in vb I suddenly thought what about making an extension method on string to execute data access code. <Extension()> Function Execute(ByVal s As String) As Data.DataTable 'make code here to access the database .. 'read connectionstring from the .config file End Function ...
I'm trying to include an extension methods static class in a dynamically generated assembly, except that i keep getting a compiler error of 'Type expected' at line 6, column 28, which happens to be on the word 'this'. If i remove 'this' no error is returned (but then it is not an extension method). public static void CodeDomDooDad() ...
I can't seem to figure out the LINQ Join extension method... I have the following LINQ inline query: var cc = from z in zipcodes join c in contactsRepo.UDF_SelectSome() on z.Zipcode equals c.Zip What is the equivalent of this in LINQ-extension-method syntax? ...
Is it possible to create an extension method that returns the instance that is invoking the extension method? I would like to have an extension method for anything that inherits from ICollection<T>, returns the object. Much like how jQuery always returns the jquery object. public static object AddItem<T>(this ICollection<T> collection...
Hello It is a little hard to explain it with my poor english but i will try. In below list sequence, if a item first field has same value with another item first field value but not same second fields. As result i want to collect items which has same first field but not second fields. It looks quite easy but i think it is not any.Cons...
Can I make an Extension method for all the subclasses of System.Object (everything)? Example: <Extension> Public Function MyExtension(value As Object) As Object Return value End Function The above functions won't work for object instance: Dim myObj1 As New Object() Dim myObj2 = myObj1.MyExtension() The compiler does not accept...
Is there a way to aggregate multiple aggregates to 1 time span? Dim times = { New TimeSpan(1, 0, 0), New TimeSpan(1, 10, 0), New TimeSpan(1, 50, 0), New TimeSpan(0, 20, 0), New TimeSpan(0, 10, 0) } Dim sum As New TimeSpan For Each ts In times sum = sum.Add(ts) Next 'That's what I desire: sum = times.Sum sum = times.Aggreg...
After using F# for a few small problems, I've found it helpful for myself to think of C# extension methods as 'a way of turning the . into a pipe-forward operator'. For example, given a sequence of Int32s named ints, the C# code: ints.Where(i => i > 0) .Select(i => i * i) is similar to the F# code let where = Seq.filter let sele...
Hi, I am writing a simple generic update extension for IEnumerable, this method used to join given 2 List of business objects or dictionaries using the given keys and updating the specific field. public static void Update<TOuter, TInner, TKey>(this IEnumerable<TOuter> outer, IEnumerable<TInner> Inner, Func<TOuter, TKey> OuterKeySelecto...
Extension 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...
My Title may be slightly off but here is what I am trying to do. I have a L2S Method that would be for every table that I would like to write once. This is to set a soft lock column where I will also need a Read and UnLock method. Here is what I have so far: public static void LockRow(string TableName, int TablePrimaryKey) { ...
So at work I was using an API that we didn't write, and one of the methods took a delegate. For one reason or another, the idea came to me that I have an extension method that fits that signature, so I was wondering if it would work. I was sure it wouldn't but much to my surprise, it did. Allow me to demonstrate: Say I have these classe...
Why cannot I see this enum extension method? (I think I'm going crazy). File1.cs namespace Ns1 { public enum Website : int { Website1 = 0, Website2 } } File2.cs using Ns1; namespace Ns2 { public class MyType : RequestHandler<Request, Response> { public override Res...
Hi, I am attempting to filter a list based on a predicate Func. I use Func to filter the complete list and return the result of the operation. I then need to determine which MachineActions appear in the complete list but not the filtered list. static void Main(string[] args) { var allActions = new List<MachineAction> ...
I can't make any sense of the MSDN documentation for this overload of the Where method that accepts a predicate that has two arguments where the int, supposedly, represents the index of the source element, whatever that means (I thought an enumerable was a sequence and you couldn't see further than the next item, much less do any indexin...
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. What the hell is going on? ...
Premise When using code analysis (or fxCop) with C# optional parameters you can get a warning of CA1026. The short reason1 for this is not suppling all parameters with a default value. The declaration below rightly generates this warning public Color GetColor(bool red, bool blue = true, bool green = true) However there is a situatio...
I'm not for sure how the ControlCollection of ASP.Net works, so maybe someone can shed some light on this for me. I recently discovered the magic that is extension methods and Linq. Well, I was very sad to find that this isn't valid syntax var c=Controls.Where(x => x.ID=="Some ID").SingleOrDefault(); However from what I can tell, Co...