Questions tagged [interface-implementation]
137 questions
86
votes
5 answers
What interfaces do all arrays implement in C#?
As a new .NET 3.5 programmer, I started to learn LINQ and I found something pretty basic that I haven't noticed before:
The book claims every array implements IEnumerable (obviously, otherwise we couldn't use LINQ to objects on arrays...). When I…

ET.
- 1,899
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72
votes
6 answers
How do you quickly find the implementation(s) of an interface's method?
Is there a quick way to find all of the implementations of, not references to, an interface's method/property/etc? Here's some sample code:
public class SomeClass : IBaseClass
{
public Int32 GetInt()
{
return 1;
}
}
public interface…

Beep beep
- 18,873
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26
votes
6 answers
How many interfaces are allowed to be implemented?
In C#:
How many interfaces a class can implement at the same time?
public class MyClass: IInteferface_1, IInterface_2, ... , IInterface_N
{
}
Is there a limit for N?
Don't worry I don't want to implement or maintain such an object. I was just…

Liviu Mandras
- 6,540
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21
votes
3 answers
Interface implemented twice "types may unify"; why does this workaround work?
I've run into a compiler error when attempting to implement an interface twice for the same class like so:
public class Mapper : IMapper, IMapper
{
/* implementation for IMapper here. */
/* implementation for…

fooser
- 822
- 6
- 14
20
votes
1 answer
Unexpected behavior of a C# 8.0 default interface member
Consider the following code:
interface I {
string M1() => "I.M1";
string M2() => "I.M2";
}
abstract class A : I {}
class C : A {
public string M1() => "C.M1";
public virtual string M2() => "C.M2";
}
class Program {
static void…

Bartosz
- 461
- 2
- 9
13
votes
0 answers
Two parameters causes 'Method in Type does not have an implementation' Exception?
I have an solution with a number of projects.
Relevant for the question is an API class library, a CustomTriggers class library and a web site.
Both CustomTriggers and web site references API.
CustomTriggers implements Interface ITrigger located in…

volapture
- 131
- 1
- 1
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13
votes
4 answers
Does libxml2 support XPath 2.0 or not?
I've tried to use the XPath 2.0 exp //span/string(.) in libxml2, but it doesn't work.
So, my question is: does libxml2 support XPath 2.0 or not?

Sefran
- 375
- 6
- 24
13
votes
2 answers
In C#, is it possible to implement an interface member using a member with a different name, like you can do in VB.NET?
Ok, this is a question I'm asking, not as in demonstrating good coding practices (this actually could be considered a bad practice) but rather in regards to 'can' it be done at all.
That said, in VB.NET you implement an interface like this...
Sub…

Mark A. Donohoe
- 28,442
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- 286
13
votes
2 answers
Choose a concrete implementation at runtime with Java 8
I'm not clear about where to put the if/switch when choosing what implementation/subclass to instantiate, specially when considering that now interfaces can have static methods.
Let's say I have a service, a type defined by an interface and a couple…

user3748908
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12
votes
2 answers
PHP interface implementation rejects subclasses on parameters
consider this:
class A{}
class B extends A{}
interface I{
// expects object instanceof A
function doSomething(A $a);
}
class C implements I
{
// fails ????
function doSomething(B $b){}
}
In my conception the above should work but it doesn't…

fabio
- 2,269
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12
votes
2 answers
What are the API that does implement JSR-353 (JSON)
I just found out that Jackson does not implement JSR-353 and we already designed the module.. so i am in a desperate hurry to find a replacement of this API to begin working ! :D
I searched an API that implements the standard but could not find any…

maher.belkh
- 473
- 2
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11
votes
4 answers
Can a class extend the Collection object?
I'm trying to extend functionality of the VBA Collection object in a new class and make this class an inheritant of Collection, but the Implements Collection statement gives me the following error:
Bad interface for Implements: method
has…

Jean-François Corbett
- 37,420
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11
votes
3 answers
How to create a custom observable collection using ConcurrentDictionary, INotifyCollectionChanged, INotifyPropertyChanged
I am trying to create an ObservableConcurrentDictionary. This object will be used in a multithreaded application, and it's data is used to populate a control via the controls ItemsSource property.
This is the implementation i have come up…

c0D3l0g1c
- 3,020
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- 71
11
votes
5 answers
Avoid explicit type casting when overriding inherited methods
I have a base abstract class that also implements a particular interface.
public interface IMovable
where TEntity: class
where T: struct
{
TEntity Move(IMover moverProvider);
}
public abstract class Animal :…

Robert Koritnik
- 103,639
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- 404
11
votes
3 answers
in MVC4 shows and error that I have to implement some Interface but I am already done it
I am trying to create own filter attribute in order to support multilinguality.
The idea is simple. URL stands for language.
*http://host.ext/en/rest_of_the_url* will open in English and
*http://host.ext/hy/rest_of_the_url* will open in…

TIKSN
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