A program written in Lesson 4 of the following introductory C# console programming series:http://williammillerservices.com/windows-c-console-programming/

age.cs

using System;
 /*
from Lesson 4 of C# console programming tutorial series at following URL:
http://williammillerservices.com/windows-c-console-programming/
demonstrates input data validation and parsing to int
GitHub gist -> https://gist.github.com/kyrathasoft/a6ead63e6832361086dc69a6487de81d
Pastebin.com -> https://pastebin.com/ySY7crrg
*/
namespace MyNamespace
{
    class MyClass
    {
        static void Main()
        {
			//get user's name
            Console.Write("What is your name? ");
            string sName = Console.ReadLine();
            
			//get user's location
			Console.Write("And where are you from? ");
            string sFrom = Console.ReadLine();

			
			bool blnValid = false; //a true/false flag for use in the while loop
			int iAge = 0; //initialize age to zero; user will change this value
			
			//loop until user enters a valid integer
			while(!blnValid){
				try{
					Console.Write("What is your age? ");
					string sAge = Console.ReadLine();
					iAge = Int32.Parse(sAge);
					if(iAge < 4){ 
						Console.Write(iAge.ToString() + "? I don't think so. "); 						
						blnValid = false;
					}else{
						blnValid = true;
						if(iAge >= 80){
							Console.WriteLine("You're {0} and learning C# at that age? Respect!", iAge.ToString());
						}
					}
				}catch{
					Console.WriteLine("Uh, that's not your age...");					
				}				
			}

			//finally, report data back to user by printing to console
            Console.Write("Summary: You are {0}. You are from {1}, and are ", sName, sFrom);
            Console.WriteLine("{0} years old.", iAge.ToString());
        }
    }
}