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Using generics in C # extension functions

I am using generics to translate Java code to C # and sorting container issues:

public static class MyExtensions
{
    public static void add(this List<object> list, object obj)
    {
        list.Add(obj);
    }
    public static void add(this List<string> list, string s)
    {
        list.Add(s);
    }
}

It looks like generics get lost when comparing arguments and both methods collide. I would like any advice on whether generics can be used this way. Is it possible to support all list operations with one:

    public static void add(this List<object> list, object obj)
    {
        list.Add(obj);
    }

eg?

SUMMARY All answers have the same solution. The list can be referred to as ICollection. Overall, this is probably not a good idea for production code.

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6 answers


What about:

public static void add<T>(this IList<T> list, T value)
{
    list.Add(value);
}


(actually it can be ICollection<T>

, since it (does not IList<T>

) define Add(T)

)

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You tried:

public static void add<T>(this List<T> list, T obj)
{
    list.Add(obj);
}


I'm not sure if you want to restrict it to a class or not, but it should do what you describe.

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You mean this:

public static void add<T>(this List<T> list, T obj)
{
    list.Add(obj);
}
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I think Mark Gravell answered this in the best possible way , but I'll add:

Don't do it at all. No benefits:

myList.add(obj);

against

myList.add(obj);

The only "advantage" here is that your final C # will not look right to most developers. If you're going to port from Java to C #, it's worth spending the extra time to make your methods look and work like native .NET methods.

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The most versatile way:

public static void add<T>(this ICollection<T> list, T obj) // use ICollection<T>
{
    list.Add(value);
}
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@Dreamwalker, you mean? list.Add(obj);

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