What's the Best Way to Add One Item to an IEnumerable?

Question

Here\'s how I would add one item to an IEnumerable object:

//Some IEnumerable object
IEnumerable arr = new string[] { \"ABC\", \"DEF\"         


        

Answer 1

Append() - is exactly what you need, it has been added to the .NET Standard (in 2017), so you no longer need to write your own extension methods. You can simply do this:

arr = arr.Append("JKL");

Since .NET is open source, here you can look on the implementation (it is more sophisticated than custom methods suggested above): https://github.com/dotnet/runtime/blob/master/src/libraries/System.Linq/src/System/Linq/AppendPrepend.cs