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C# Introduction

Iskander Ismagilov
Iskander Ismagilov
13,298 Points
Posted by Iskander Ismagilov
Iskander Ismagilov
13,298 Points

Make an array extension

Does it turn out that you can't make extension method for array of any type cause array is not a generic type?

1 Answer

Max Eremin
.a{fill-rule:evenodd;}techdegree
Max Eremin
Full Stack JavaScript Techdegree Student 18,433 Points

Hi, Iskander! In C# you can create an extension for any collection type (not necessarily generic). As simple example:

public static class Extensions 
{
    public static T Extension<T>(this T array) where T : IEnumerable
    {
        // do something
        return array;
    }

    public static int[] Extension(this int[] array) 
    {
        // do something
        return array;
    }
}
Iskander Ismagilov
Iskander Ismagilov
13,298 Points
Iskander Ismagilov
Iskander Ismagilov
13,298 Points

Thank you, Max! Your example with type constraint helped me to understand how to make extensions for array. Also, previously I was confused about treating array as IEnumerable<T>, but then I found that array do implements IEnumerable<T> from the doc.