Select case in LINQ [duplicate]

Answer 1

Use something like that:

class AgeHelper
{
    private static Dictionary, string> dic = new Dictionary, string>
    {
        { Enumerable.Range(0, 10), "0-25" },
        { Enumerable.Range(10, 5), "26-40" },
        { Enumerable.Range(15, 35), "60-100" }
    };

    public string this[int age]
    {
        get
        {
            return dic.FirstOrDefault(p => p.Key.Contains(age)).Value ?? "50+";
        }
    }
}

The rest of @Botz3000's answer:

from u in users
let range = new AgeHelper()[u.Age]
...