String input = Console.ReadLine();
int selectedOption;
if(int.TryParse(input, out selectedOption))
{
switch(selectedOption)
{
case 1:
//your code here.
break;
case 2:
//another one.
break;
//. and so on, default..
}
}
else
{
//print error indicating non-numeric input is unsupported or something more meaningful.
}