Reverse Text in C# (Source Code)

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Reverse_String
{
    public partial class frmReverseString : Form
    {
        public frmReverseString()
        {
            InitializeComponent();
        }

        private void frmReverseString_Load(object sender, EventArgs e)
        {
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string typedString = txtInput.Text;
            if (typedString == "")
            {
                MessageBox.Show("Please enter some text.");
            }
            else
            {
            string reversedString = (StringHelper.ReverseString(typedString));
            MessageBox.Show(typedString + " reversed is " + reversedString);
            }
        }
    }
}

static class StringHelper
{
    public static string ReverseString(string s)
    {
        char[] arr = s.ToCharArray();
        Array.Reverse(arr);
        return new string(arr);
    }
}