Convert string into Title Case in C# by Extension method Without using TextInfo class

public static class StringExtension

    {

        /// <summary>

        /// Use to convert string in Title Case

        /// </summary>

        /// <param name="str"></param>

        /// <returns></returns>

        public static string ToTitleCase(this string str)

        {

            if (!String.IsNullOrEmpty(str))

                return String.Join(" ", str.Split(' ').Select(i => i.Length > 0 ? (i.Substring(0, 1).ToUpper() + i.Substring(1).ToLower()) : i).ToArray());

            return str;

        }

    }

    class Program

    {

        static void Main(string[] args)

        {

            string str = "convert STRING into title case in c#";

            Console.WriteLine(str.ToTitleCase());

            Console.ReadLine();

        }

    }

Output: