Change Text Case

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

namespace ChangeTextCase
{
	public partial class Form1 : Form
	{
		public Form1()
		{
			InitializeComponent();
		}

		private void btnCopy_Click(object sender, EventArgs e)
		{
			txtDestination.SelectAll();
			txtDestination.Copy();
		}

		private void btnChangeCase_Click(object sender, EventArgs e)
		{
			string sText = txtSource.Text;
			txtSource.Text = "";
			txtDestination.Text = "";

			#region Get the culture property of the thread.
			CultureInfo cultureInfo = Thread.CurrentThread.CurrentCulture;
			//Create TextInfo object.
			TextInfo textInfo = cultureInfo.TextInfo;
			#endregion Get the culture property of the thread.

			#region Title case
			if (rbTitleCase.Checked == true)
			{
				sText = sText.ToLower();
				txtDestination.Text = textInfo.ToTitleCase(sText);
			}
			#endregion Title case

			#region Lower case
			if (rbLowerCase.Checked == true)
			{
				txtDestination.Text = sText.ToLower();
			}
			#endregion Lower case

			#region Upper case
			if (rbUpperCase.Checked == true)
			{
				txtDestination.Text = sText.ToUpper();
			}
			#endregion Upper case


			#region Remove Line Break - Start
			if (rbRemoveLineBreak.Checked == true)
			{
				if (ckRemoveTabs.Checked == false)
				{
					//txtDestination.Text = sText.Replace(System.Environment.NewLine, sText);
					string replaceWith = "";
					txtDestination.Text = sText.Replace("rn", replaceWith).Replace("n", replaceWith).Replace("r", replaceWith);
				}
				else
				{
					//txtDestination.Text = sText.Replace(System.Environment.NewLine, sText);
					string replaceWith = "";
					txtDestination.Text = sText.Replace("rn", replaceWith).Replace("n", replaceWith).Replace("r", replaceWith).Replace("t", replaceWith).Replace(" '", "'");
				}
			}
			#endregion  Remove Line Break - Stop
		}
	}
}