do while loop treats same as while loop but only differences between them is that, do while executes at least one time. The code executes first then check for specified loop condition. But in while loop, the specified loop condition evaluated first then executes the code.

using System;
namespace dowhile
{
    class Program
    {
        static void Main(string[] args)
        {
            int Number, i, Result;
            Number = 12;
            i = 1;
            do
            {
                Result = Number * i;
                Console.WriteLine("{0} x {1} = {2}", Number, i, Result);
                i++;
            }           
            while (i <= 12);
            Console.ReadLine();
        }
    }
}