Chameleon - Connection Settings Manager

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

namespace ControlLib
{
    public class IpNumericDigit : TextBox
    {
        public delegate void SelectNextDelegate();
        public event SelectNextDelegate SelectNext;

        public delegate void SelectPreviousDelegate();
        public event SelectPreviousDelegate SelectPrevious;

        public IpNumericDigit()
        {
            this.Width = 30;
            this.MaxLength = 3;
            this.TextAlign = HorizontalAlignment.Center;
        }
        private bool _Use223AsMax = false;

        public bool Use223AsMax
        {
            get { return _Use223AsMax; }
            set { _Use223AsMax = value; }
        }
        protected override void OnKeyPress(KeyPressEventArgs e)
        {
            if ((int)e.KeyChar >= 48 && (int)e.KeyChar <= 57)
            {
                e.Handled = false;
            }
            if ((int)e.KeyChar == 32)
            {
                if (SelectNext != null)
                {
                    SelectNext();
                }
                e.Handled = false;
            }
            if ((int)e.KeyChar == 8)
            {
                if (this.Text.Length == 0)
                {
                    if (SelectPrevious != null)
                    {
                        SelectPrevious();
                    }
                }
                e.Handled = false;
            }
            base.OnKeyPress(e);
        }
        protected override void OnKeyDown(KeyEventArgs e)
        {
            if (e.KeyValue == 39)
            {
                if (this.SelectionStart == this.Text.Length && Validate())
                {
                    if (SelectNext != null)
                    {
                        SelectNext();
                    }
                }
            }
            else if (e.KeyValue == 37)
            {
                if (this.SelectionStart == 0)
                {
                    if (SelectPrevious != null)
                    {
                        SelectPrevious();
                    }
                }
            }
            base.OnKeyDown(e);
        }
        protected override void OnTextChanged(EventArgs e)
        {
            if (this.Text.Trim().Length == 3)
            {
                if (Validate())
                {
                    if (SelectNext != null)
                    {
                        SelectNext();
                    }
                }
            }
            base.OnTextChanged(e);
        }
        private bool Validate()
        {
            int minValue = 0;
            int maxValue = 255;
            if (Use223AsMax)
            {
                minValue = 1;
                maxValue = 223;
            }
            if (this.Text.Trim().Length > 0)
            {
                if (!(Convert.ToInt32(this.Text) >= minValue && Convert.ToInt32(this.Text) <= maxValue))
                {
                    MessageBox.Show(minValue.ToString() + " ile " + maxValue.ToString() + " aras� bir say� giriniz");
                    this.Text = maxValue.ToString();
                    this.Select(0, 0);
                    return false;
                }
                else
                {
                    return true;
                }
            }
            else
            {
                return true;
            }
        }
    }
}