WaterMark TextBox For Desktop Applications Using C#, .NET 3.5 and VS2008

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Drawing;

namespace wmgCMS
{
    class WaterMarkTextBox : TextBox
    {
        private Font oldFont = null;
        Timer timer = new Timer();

        #region Attributes 
            private Color _waterMarkColor = Color.Gray;
            public Color WaterMarkColor
            {
                get { return _waterMarkColor; }
                set { _waterMarkColor = value; if (this.Created) Refresh(); }
            }

            private string _waterMarkText = "Water Mark";
            public string WaterMarkText
            {
                get { return _waterMarkText; }
                set { _waterMarkText = value; if (this.Created) Refresh(); }
            }
            
            //Private attribute
            private Boolean _waterMarkTextEnabled = false;
            private Boolean WaterMarkTextEnabled
            {
                get { return _waterMarkTextEnabled; }
                set { _waterMarkTextEnabled = value; }
            }
        #endregion

        //Default constructor
        public WaterMarkTextBox()
        {
            JoinEvents(true);
        }

        //Override OnPaint
        protected override void OnPaint(PaintEventArgs args)
        {
            // Use the same font that was defined in base class
            System.Drawing.Font drawFont = new System.Drawing.Font(Font.FontFamily, Font.Size, Font.Style, Font.Unit);
            //Create new brush with gray color or 
            SolidBrush drawBrush = new SolidBrush(WaterMarkColor);//use Water mark color
            //Draw Text or WaterMark
            args.Graphics.DrawString((WaterMarkTextEnabled ? WaterMarkText : Text), drawFont, drawBrush, new PointF(0.0F, 0.0F));
            base.OnPaint(args);
        }

        private void JoinEvents(Boolean join)
        {
            if (join)
            {
                this.TextChanged += new System.EventHandler(this.WaterMark_Toggel);
                this.LostFocus += new System.EventHandler(this.WaterMark_Toggel);
                this.FontChanged += new System.EventHandler(this.WaterMark_FontChanged);
                //No one of the above events will start immeddiatlly 
                //TextBox control still in constructing, so,
                //Font object (for example) couldn't be catched from within WaterMark_Toggle
                //So, call WaterMark_Toggel through timer_Tick after TextBox is totally created
                //No doupt, it will be only one time call then kill the timer object
                timer.Tick += new EventHandler(timer_Tick);
                timer.Interval = 100;
                timer.Start();
            }
        }

        private void timer_Tick(object sender, EventArgs e)
        {
            if (Created)
            {
                WaterMark_Toggel(null, null);
                timer.Stop();
                timer = null;
            }
        }

        private void WaterMark_Toggel(object sender, EventArgs args )
        {
            if (this.Text.Length <= 0)
                EnableWaterMark();
            else
                DisbaleWaterMark();
        }

        private void EnableWaterMark()
        {
            //Save current font until returning the UserPaint style to false (NOTE: It is a try and error advice)
            oldFont = new System.Drawing.Font(Font.FontFamily, Font.Size, Font.Style, Font.Unit);
            //Enable OnPaint event handler
            this.SetStyle(ControlStyles.UserPaint, true);
            this.WaterMarkTextEnabled = true;
            //Triger OnPaint immediatly
            Refresh();
        }

        private void DisbaleWaterMark()
        {
            //Disbale OnPaint event handler
            this.WaterMarkTextEnabled = false;
            this.SetStyle(ControlStyles.UserPaint, false);
            //Return back oldFont if existed
            if(oldFont != null)
                this.Font = new System.Drawing.Font(oldFont.FontFamily, oldFont.Size, oldFont.Style, oldFont.Unit);
        }

        private void WaterMark_FontChanged(object sender, EventArgs args)
        {
            if (WaterMarkTextEnabled)
            {
                oldFont = new System.Drawing.Font(Font.FontFamily,Font.Size,Font.Style,Font.Unit);
                Refresh();
            }
        }
    }
}