using System;

public class Program

{

    public IEnumerable<string> GetNames() { ... }

    public void ProcessNames()

    {

        var names = GetNames();

        if (!names.Any())

        {

            return;

        }

​

        var formatted = names.Select((x, i) => $"{x}-{i}");

        foreach (var item in formatted)

        {

            ...

        }

    }

}