Masked TextBox Host : MaskedTextBox : GUI Windows Form C# Source Code

    

/*
User Interfaces in C#: Windows Forms and Custom Controls
by Matthew MacDonald

Publisher: Apress
ISBN: 1590590457
*/


using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace MaskedTextBoxHost
{
    /// <summary>
    /// Summary description for MaskedTextBoxHost.
    /// </summary>
    public class MaskedTextBoxHost : System.Windows.Forms.Form
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;

        public MaskedTextBoxHost()
        {
            //
            // Required for Windows Form Designer support
            //
            InitializeComponent();

            //
            // TODO: Add any constructor code after InitializeComponent 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 );
        }

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            // 
            // MaskedTextBoxHost
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(292, 266);
            this.Name = "MaskedTextBoxHost";
            this.Text = "MaskedTextBoxHost";
            this.Load += new System.EventHandler(this.MaskedTextBoxHost_Load);

        }


        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main() 
        {
            Application.Run(new MaskedTextBoxHost());
        }

        private void MaskedTextBoxHost_Load(object sender, System.EventArgs e)
        {
            MaskedTextBox txtMask = new 
                MaskedTextBox();
            txtMask.Location = new Point(10, 10);
            txtMask.Mask = "(###) ###-####";
            this.Controls.Add(txtMask);

        }
    }
    public class MaskedTextBox : TextBox
    {
        private string mask;
        public string Mask
        {
            get
            {
                return mask;
            }
            set
            {
                mask = value;
                this.Text = "";
            }
        }

        protected override void OnKeyPress(KeyPressEventArgs e)
        {
            if (Mask != "")
            {
                // Suppress the typed character.
                e.Handled = true;

                string newText = this.Text;

                // Loop through the mask, adding fixed characters as needed.
                // If the next allowed character matches what the user has
                // typed in (a number or letter), that is added to the end.
                bool finished = false;
                for (int i = this.SelectionStart; i < mask.Length; i++)
                {
                    switch (mask[i].ToString())
                    {
                        case "#" :
                            // Allow the keypress as long as it is a number.
                            if (Char.IsDigit(e.KeyChar))
                            {
                                newText += e.KeyChar.ToString();
                                finished = true;
                                break;
                            }
                            else
                            {
                                // Invalid entry; exit and don't change the text.
                                return;
                            }
                        case "." :
                            // Allow the keypress as long as it is a letter.
                            if (Char.IsLetter(e.KeyChar))
                            {
                                newText += e.KeyChar.ToString();
                                finished = true;
                                break;
                            }
                            else
                            {
                                // Invalid entry; exit and don't change the text.
                                return;
                            }
                        default :
                            // Insert the mask character.
                            newText += mask[i];
                            break;
                    }
                    if (finished)
                    { break; }
                }

                // Update the text.
                this.Text = newText;
                this.SelectionStart = this.Text.Length;
            }
    }    
  
        protected override void OnKeyDown(KeyEventArgs e)
        {
            // Stop special characters.
            e.Handled = true;
        }

}



}