Password Protected Stream Using Decorator Pattern

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using SecureApplication.Classes;
using System.IO;

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

        private void button1_Click(object sender, EventArgs e)
        {
            PasswordProtectedStream st = new PasswordProtectedStream(new FileStream("C:/pwdsample.txt", FileMode.Create), "12345"); //create instance of our stream
            StreamWriter w = new StreamWriter(st);
            w.Write("Hye this is test"); //write some data
            w.Flush();
            w.Close();
            
            st.Close();
            st.Dispose();

            MessageBox.Show("Data Written Successfully");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            PasswordProtectedStream st = new PasswordProtectedStream(new FileStream("C:/pwdsample.txt", FileMode.Open), "12345"); //create instance of our stream, try changing a password here
            st.On_ReadComplete += new PasswordProtectedStream.ReadCompleteHandler(st_On_ReadComplete); //hook the read complete event
            
            StreamReader w = new StreamReader(st);
            w.ReadToEnd(); //read but don't display the data here, else you won't get anything useful. Readers are welcome if they can provide an implementation which enables us to read the data in usual manner, without the use of event
            w.Close();
            st.Close();
            st.Dispose();
        }

        void st_On_ReadComplete(object s, PasswordProtectedStream.ReadCompleteEventArgs e)
        {
            if (e.ReadStatus == PasswordProtectedStream.ReadCompleteEventArgs.Status.FAILURE) //if wrong password
                MessageBox.Show("Wrong Password");
            else
                MessageBox.Show("Data Read back: " + Encoding.ASCII.GetString(e.Data)); //display data
        }
    }
}