Artigo Manipulando Strings com C# - StringBuilder

Program.cs

using System;
using System.Text;

namespace ManipulandoStrings
{
    class Program
    {
        static void Main(string[] args)
        {
            var nomes = new string[] { "Luis", "Francisco", "Leonardo", "Ivan", "Lucas", "Paulo" };
            var stringBuilder = new StringBuilder();

            foreach (var nome in nomes) {
                stringBuilder.AppendLine($"Seja bem-vindo {nome}");
            }

            Console.WriteLine(stringBuilder);
        }
    }
}