Closures

private static void DynamicAdd()
{
    var m5 = GetMultiX(5);
    var m10 = GetMultiX(10);
    Console.WriteLine(m5(10));
    Console.WriteLine(m10(10));
}

private static Func<int, int> GetMultiX(int staticVal)
{
    return x => staticVal * x;
}

m5 returns 50 beacuse 5 * 10.
m10 returns 100 beacuse 10 * 10.