using System;

using org.matheval;

public class Program

{

    public static void Main()

    {

        Expression expr = new Expression("SWITCH(name,1,'apple',2,'mango',3,'banana','N/A')");

        //Bind variable

        expr.Bind("name", 2);

        //eval

        String value = expr.Eval<String>(); //return "mango"        

        Console.WriteLine(value);

    }

}