Make first letter of a string upper case in C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace FirstLetterUpperCaseString
{
    class FirstLetterUpperCase
    {
        static void Main(string[] args)
        {
            string a = "akshay upadhyay";
            Console.WriteLine("Before operation : " + a);

            //Converting string to character array
            char[] s = a.ToCharArray();

            //Convert the first char to upper case
            s[0] = char.ToUpper(s[0]);

            //Reconverting array to string
            a = new string(s);
            Console.WriteLine("After operation : " + a);

            Console.Read();
        }
    }
}