IPBoxControl 开发手记（二）

    如果哪位发现什么问题和bug，请多多指出，我会及时修改。谢谢！

/**//*
 * Purpose: IPAddress TextBox Control.
 * Author: Vincent
 * Date: 2004-10-29
 *
 */

using System;
using System.Windows.Forms;

namespace Sci.Vincent.Controls
{
    /**//// <summary>
    /// IP Address Box Control.
    /// </summary>
    public class IPBox : System.Windows.Forms.UserControl
    {
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.Label label2;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.Label label3;
        private System.Windows.Forms.TextBox textBox3;
        private System.Windows.Forms.TextBox textBox4;

        /**//// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;

        private System.Windows.Forms.Panel panel1;

        private const int DEFAULT_WIDTH_SIZE = 136;
        private const int DEFAULT_HEIGHT_SIZE = 20;
        private string _text = "";
        private bool _isAllowWarn = true;
        private Languages _language = Languages.English;

        /**//// <summary>
        /// Usable languages enumeration.
        /// </summary>
        public enum Languages
        {
            /**//// <summary>
            /// English language
            /// </summary>
            English,
            /**//// <summary>
            /// Chinese language
            /// </summary>
            Chinese
        }


        /**//// <summary>
        /// Creates an instance of the IPBox class.
        /// </summary>
        public IPBox()
        {
            // This call is required by the Windows.Forms Form Designer.
            InitializeComponent();

            // TODO: Add any initialization after the InitComponent call

        }

        /**//// <summary>
        /// Clean up any resources being used.
        /// </summary>
        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                if (components != null)
                    components.Dispose();
            }
            base.Dispose(disposing);
        }

        Component Designer generated code#region Component Designer generated code

        /**//// <summary>
        /// Required method for Designer support - do not modify 
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.label1 = new System.Windows.Forms.Label();
            this.label2 = new System.Windows.Forms.Label();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.label3 = new System.Windows.Forms.Label();
            this.textBox3 = new System.Windows.Forms.TextBox();
            this.textBox4 = new System.Windows.Forms.TextBox();
            this.panel1 = new System.Windows.Forms.Panel();
            this.panel1.SuspendLayout();
            this.SuspendLayout();
            // 
            // textBox1
            // 
            this.textBox1.BorderStyle = System.Windows.Forms.BorderStyle.None;
            this.textBox1.Location = new System.Drawing.Point(8, 0);
            this.textBox1.MaxLength = 3;
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(20, 13);
            this.textBox1.TabIndex = 0;
            this.textBox1.Text = "";
            this.textBox1.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
            this.textBox1.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.textBox1_KeyPress);
            // 
            // label1
            // 
            this.label1.BackColor = System.Drawing.SystemColors.Window;
            this.label1.Location = new System.Drawing.Point(32, 0);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(8, 14);
            this.label1.TabIndex = 1;
            this.label1.Text = ".";
            this.label1.TextAlign = System.Drawing.ContentAlignment.TopCenter;
            // 
            // label2
            // 
            this.label2.BackColor = System.Drawing.SystemColors.Window;
            this.label2.Location = new System.Drawing.Point(64, 0);
            this.label2.Name = "label2";
            this.label2.Size = new System.Drawing.Size(8, 14);
            this.label2.TabIndex = 3;
            this.label2.Text = ".";
            this.label2.TextAlign = System.Drawing.ContentAlignment.TopCenter;
            // 
            // textBox2
            // 
            this.textBox2.BorderStyle = System.Windows.Forms.BorderStyle.None;
            this.textBox2.Location = new System.Drawing.Point(40, 0);
            this.textBox2.MaxLength = 3;
            this.textBox2.Name = "textBox2";
            this.textBox2.Size = new System.Drawing.Size(20, 13);
            this.textBox2.TabIndex = 2;
            this.textBox2.Text = "";
            this.textBox2.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
            this.textBox2.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.textBox2_KeyPress);
            // 
            // label3
            // 
            this.label3.BackColor = System.Drawing.SystemColors.Window;
            this.label3.Location = new System.Drawing.Point(96, 0);
            this.label3.Name = "label3";
            this.label3.Size = new System.Drawing.Size(8, 14);
            this.label3.TabIndex = 5;
            this.label3.Text = ".";
            this.label3.TextAlign = System.Drawing.ContentAlignment.TopCenter;
            // 
            // textBox3
            // 
            this.textBox3.BorderStyle = System.Windows.Forms.BorderStyle.None;
            this.textBox3.Location = new System.Drawing.Point(72, 0);
            this.textBox3.MaxLength = 3;
            this.textBox3.Name = "textBox3";
            this.textBox3.Size = new System.Drawing.Size(20, 13);
            this.textBox3.TabIndex = 4;
            this.textBox3.Text = "";
            this.textBox3.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
            this.textBox3.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.textBox3_KeyPress);
            // 
            // textBox4
            // 
            this.textBox4.BorderStyle = System.Windows.Forms.BorderStyle.None;
            this.textBox4.Location = new System.Drawing.Point(104, 0);
            this.textBox4.MaxLength = 3;
            this.textBox4.Name = "textBox4";
            this.textBox4.Size = new System.Drawing.Size(20, 13);
            this.textBox4.TabIndex = 6;
            this.textBox4.Text = "";
            this.textBox4.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
            this.textBox4.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.textBox4_KeyPress);
            // 
            // panel1
            // 
            this.panel1.BackColor = System.Drawing.SystemColors.Window;
            this.panel1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
      &