[c# win] มันอะไรกันนักหนาเนี่ย image + picturebox เนี่ย

namespace ImageGallery
{
    partial class Form1
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form 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.ImageListBox = new System.Windows.Forms.ListBox();
            this.PictureBox1 = new System.Windows.Forms.PictureBox();
            this.AddButton = new System.Windows.Forms.Button();
            this.DeleteButton = new System.Windows.Forms.Button();
            ((System.ComponentModel.ISupportInitialize)(this.PictureBox1)).BeginInit();
            this.SuspendLayout();
            // 
            // ImageListBox
            // 
            this.ImageListBox.FormattingEnabled = true;
            this.ImageListBox.Location = new System.Drawing.Point(13, 42);
            this.ImageListBox.Name = "ImageListBox";
            this.ImageListBox.Size = new System.Drawing.Size(156, 264);
            this.ImageListBox.TabIndex = 0;
            this.ImageListBox.SelectedIndexChanged += new System.EventHandler(this.ImageListBox_SelectedIndexChanged);
            // 
            // PictureBox1
            // 
            this.PictureBox1.Location = new System.Drawing.Point(175, 13);
            this.PictureBox1.Name = "PictureBox1";
            this.PictureBox1.Size = new System.Drawing.Size(305, 293);
            this.PictureBox1.TabIndex = 1;
            this.PictureBox1.TabStop = false;
            this.PictureBox1.Click += new System.EventHandler(this.PictureBox1_Click);
            // 
            // AddButton
            // 
            this.AddButton.Location = new System.Drawing.Point(13, 13);
            this.AddButton.Name = "AddButton";
            this.AddButton.Size = new System.Drawing.Size(75, 23);
            this.AddButton.TabIndex = 2;
            this.AddButton.Text = "Add";
            this.AddButton.UseVisualStyleBackColor = true;
            this.AddButton.Click += new System.EventHandler(this.AddButton_Click);
            // 
            // DeleteButton
            // 
            this.DeleteButton.Location = new System.Drawing.Point(94, 13);
            this.DeleteButton.Name = "DeleteButton";
            this.DeleteButton.Size = new System.Drawing.Size(75, 23);
            this.DeleteButton.TabIndex = 3;
            this.DeleteButton.Text = "Delete";
            this.DeleteButton.UseVisualStyleBackColor = true;
            this.DeleteButton.Click += new System.EventHandler(this.DeleteButton_Click);
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(494, 320);
            this.Controls.Add(this.DeleteButton);
            this.Controls.Add(this.AddButton);
            this.Controls.Add(this.PictureBox1);
            this.Controls.Add(this.ImageListBox);
            this.Name = "Form1";
            this.Text = "Image Gallery";
            this.Load += new System.EventHandler(this.Form1_Load);
            ((System.ComponentModel.ISupportInitialize)(this.PictureBox1)).EndInit();
            this.ResumeLayout(false);

        }

        #endregion

        private System.Windows.Forms.ListBox ImageListBox;
        private System.Windows.Forms.PictureBox PictureBox1;
        private System.Windows.Forms.Button AddButton;
        private System.Windows.Forms.Button DeleteButton;
    }
}

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 System.IO;

namespace ImageGallery
{
    public partial class Form1 : Form
    {
        private const string SecretKey = "www.thaicreate.com";
        private string ImageDirectoryPath;
        private DataTable DtImage;

        public Form1()
        {
            InitializeComponent();

            ImageDirectoryPath = string.Format("{0}\\Images", Application.StartupPath);

            DtImage = new DataTable();
            DtImage.Columns.Add(new DataColumn("ImageName", System.Type.GetType("System.String")));
            DtImage.Columns.Add(new DataColumn("ImagePath", System.Type.GetType("System.String")));
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            DirectoryInfo ImageDirectory = new DirectoryInfo(ImageDirectoryPath);

            ImageListBox.DisplayMember = "ImageName";

            if (ImageDirectory.Exists)
            {
                foreach (FileInfo imageFile in ImageDirectory.GetFiles())
                {
                    string ImageName = imageFile.Name.Substring(0, imageFile.Name.Length - 10);
                    string ImagePath = string.Format("{0}\\{1}", ImageDirectoryPath, imageFile.Name);

                    DataRow Dr = DtImage.NewRow();
                    Dr["ImageName"] = ImageName;
                    Dr["ImagePath"] = ImagePath;
                    DtImage.Rows.Add(Dr);
                }

                ImageListBox.DataSource = DtImage;

                if (DtImage.Rows.Count > 0)
                    DisplayImage(DtImage.Rows[0]["ImagePath"].ToString());
            }
        }

        private void AddButton_Click(object sender, EventArgs e)
        {
            OpenFileDialog openImageDialog = new OpenFileDialog();
            openImageDialog.FileName = string.Empty;
            openImageDialog.Filter = "Image Files (*.gif;*.jpg;*.png;*.bmp)|*.gif;*.jpg;*.png;*.bmp";
            openImageDialog.FilterIndex = 1;
            openImageDialog.RestoreDirectory = true;
            openImageDialog.Multiselect = false;

            if (openImageDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                if (DtImage.Select(string.Format("ImageName Like '{0}'", openImageDialog.SafeFileName)).Count() == 0)
                {
                    string OutputFilePath = string.Format("{0}\\{1}.encrypted", ImageDirectoryPath, openImageDialog.SafeFileName);
                    DirectoryInfo ImageDirectory = new DirectoryInfo(ImageDirectoryPath);

                    if (!ImageDirectory.Exists)
                        ImageDirectory.Create();

                    Security.EncryptFile(openImageDialog.FileName, OutputFilePath, SecretKey);

                    DataRow Dr = DtImage.NewRow();
                    Dr["ImageName"] = openImageDialog.SafeFileName;
                    Dr["ImagePath"] = OutputFilePath;
                    DtImage.Rows.Add(Dr);

                    ImageListBox.DataSource = DtImage;
                    DisplayImage(DtImage.Rows[ImageListBox.SelectedIndex]["ImagePath"].ToString());
                }
                else
                {
                    MessageBox.Show("ไม่สามารถเพิ่มไฟล์ได้เนื่องจากมีไฟล์นี้แล้ว", "ผิดพลาด", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
                }
            }
        }

        private void DeleteButton_Click(object sender, EventArgs e)
        {
            string ImagePath = DtImage.Rows[ImageListBox.SelectedIndex]["ImagePath"].ToString();

            FileInfo imageFile = new FileInfo(ImagePath);

            if (imageFile.Exists)
            {
                imageFile.Delete();

                DtImage.Rows[ImageListBox.SelectedIndex].Delete();
                DtImage.AcceptChanges();
                ImageListBox.DataSource = DtImage;

                if (ImageListBox.SelectedIndex >= 0)
                    DisplayImage(DtImage.Rows[ImageListBox.SelectedIndex]["ImagePath"].ToString());
                else
                    PictureBox1.Image = null;

                MessageBox.Show("ลบไฟล์รูปภาพนี้เรียบร้อยแล้ว", "ลบไฟล์", MessageBoxButtons.OK, MessageBoxIcon.None);
            }
            else
            {
                MessageBox.Show("ไม่สามารถลบไฟล์นี้ได้", "ผิดพลาด", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);            
            }
        }

        private void ImageListBox_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (ImageListBox.SelectedIndex >= 0)
                DisplayImage(DtImage.Rows[ImageListBox.SelectedIndex]["ImagePath"].ToString());
            else
                PictureBox1.Image = null;
        }

        private void PictureBox1_Click(object sender, EventArgs e)
        {
            if (PictureBox1.Image != null)
            {
                byte[] imageBytes = Security.DecryptStream(DtImage.Rows[ImageListBox.SelectedIndex]["ImagePath"].ToString(), SecretKey);

                Image myImage = Image.FromStream(new MemoryStream(imageBytes));

                ViewForm viewForm = new ViewForm(myImage);
                viewForm.ShowDialog();
            }
        }

        private void DisplayImage(string ImagePath)
        {
            byte[] imageBytes = Security.DecryptStream(ImagePath, SecretKey);

            Image myImage  = Image.FromStream(new MemoryStream(imageBytes));
            Size fitImageSize = ScaledImageDimensions(myImage.Width, myImage.Height, PictureBox1.Width, PictureBox1.Height);
            Bitmap imgOutput = new Bitmap(myImage, fitImageSize.Width, fitImageSize.Height);

            PictureBox1.Image = null;
            PictureBox1.SizeMode = PictureBoxSizeMode.CenterImage;
            PictureBox1.Image = imgOutput;
        }

        private Size ScaledImageDimensions(int currentImageWidth, int currentImageHeight, int desiredImageWidth, int desiredImageHeight)
        {
            /* First, we must calculate a multiplier that will be used
             * to get the dimensions of the new, scaled image. */

            double scaleImageMultiplier = 0;

            /* This multiplier is defined as the ratio of the

             * Desired Dimension to the Current Dimension.
             * Specifically which dimension is used depends on the larger
             * dimension of the image, as this will be the constraining dimension
             * when we fit to the window. */

            /* Determine if Image is Portrait or Landscape. */    
            if (currentImageHeight > currentImageWidth) /* Image is Portrait */
            {
                /* Calculate the multiplier based on the heights. */
                if (desiredImageHeight > desiredImageWidth)
                {
                    scaleImageMultiplier = (double)desiredImageWidth / (double)currentImageWidth;
                }
                else
                {
                    scaleImageMultiplier = (double)desiredImageHeight / (double)currentImageHeight;
                }
            }
            else /* Image is Landscape */
            {
                /* Calculate the multiplier based on the widths. */
                if (desiredImageWidth > desiredImageHeight)
                {
                    scaleImageMultiplier = (double)desiredImageWidth / (double)currentImageWidth;
                }
                else
                {
                    scaleImageMultiplier = (double)desiredImageHeight / (double)currentImageHeight;
                }
            }

            /* Generate and return the new scaled dimensions.

             * Essentially, we multiply each dimension of the original image
             * by the multiplier calculated above to yield the dimensions
             * of the scaled image. The scaled image can be larger or smaller
             * than the original. */

            int outputWidth = (int)(currentImageWidth * scaleImageMultiplier);
            int outputHight = (int)(currentImageHeight * scaleImageMultiplier);

            return new Size((currentImageWidth > outputWidth) ? outputWidth : currentImageWidth, (currentImageHeight > outputHight) ? outputHight : currentImageHeight);
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;

using System.IO;
using System.Runtime.InteropServices;
using System.Security.Cryptography;
using System.Text;

/// <summary>
/// Summary description for Security
/// </summary>
public class Security
{
    /// <summary>
    /// สำหรับเข้ารหัส และถอดรหัส
    /// </summary>
    public Security()
    {
        //
        // TODO: Add constructor logic here
        //
    }

    /// <summary>
    /// สร้าง Code สำหรับเปลี่ยนแปลงข้อมูลเพื่อความปลอดภัย
    /// </summary>
    /// <param name="EncryptString">ข้อความที่ต้องการเข้ารหัส</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    /// <returns>ข้อความที่เข้ารหัสแล้ว</returns>	
    public static string EncryptString(string EncryptString, string SecretKey)
    {
        MemoryStream msEncrypt = new MemoryStream();
        DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
        string secretKey = (SecretKey.Length == 8) ? SecretKey : MD5(SecretKey);

        // Key ที่ต้องใช้งานกันทั้งสองฝ่าย ข้อมูลลับ
        DES.Key = ASCIIEncoding.ASCII.GetBytes(secretKey);
        DES.IV = ASCIIEncoding.ASCII.GetBytes(secretKey);

        // ใช้ CreateEncryptor ในการเข้ารหัส
        ICryptoTransform myEncryptor = DES.CreateEncryptor();

        // ตัวแปร array สำหรับรับข้อความที่ต้องการเข้ารหัส ต้องแปลงเป็น ASCII
        byte[] pwd = ASCIIEncoding.ASCII.GetBytes(EncryptString);

        // เข้ารหัสข้อมูล ข้อมูลที่เข้ารหัสเรียบร้อยแล้วจะเก็บไว้ที่ msEncrypt
        CryptoStream myCryptoStream = new CryptoStream(msEncrypt, myEncryptor, CryptoStreamMode.Write);
        myCryptoStream.Write(pwd, 0, pwd.Length);
        myCryptoStream.Close();

        // ส่งค่าที่ encrypt แล้วกลับไป
        return Convert.ToBase64String(msEncrypt.ToArray());
    }

    /// <summary>
    /// ถอดรหัส Code
    /// </summary>
    /// <param name="DecryptString">ข้อความที่ต้องการถอดรหัส</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    /// <returns>ข้อความที่ถอดรหัสแล้ว</returns>
    public static string DecryptString(string DecryptString, string SecretKey)
    {
        MemoryStream msDecrypt = new MemoryStream();
        DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
        string secretKey = (SecretKey.Length == 8) ? SecretKey : MD5(SecretKey);

        // Key ที่ต้องใช้งานกันทั้งสองฝ่าย ข้อมูลลับ
        DES.Key = ASCIIEncoding.ASCII.GetBytes(secretKey);
        DES.IV = ASCIIEncoding.ASCII.GetBytes(secretKey);

        // ใช้ CreateDecryptor ในการเข้าถอดรหัส
        ICryptoTransform myDecryptor = DES.CreateDecryptor();

        // ตัวแปร array สำหรับรับข้อความที่ต้องการถอดรหัส ไม่ต้องแปลงเป็น ASCII
        byte[] pwd = Convert.FromBase64String(DecryptString);

        // เข้ารหัสข้อมูล ข้อมูลที่เข้ารหัสเรียบร้อยแล้วจะเก็บไว้ที่ msDecrypt
        CryptoStream cCryptoStream = new CryptoStream(msDecrypt, myDecryptor, CryptoStreamMode.Write);
        cCryptoStream.Write(pwd, 0, pwd.Length);
        cCryptoStream.Close();

        // ส่งค่าที่ decrypt แล้วกลับไป ต้องแปลงจาก ASCII ให้กลับเป็น string ก่อน
        return ASCIIEncoding.ASCII.GetString(msDecrypt.ToArray());
    }

    /// <summary>
    /// เข้ารหัสเอกสาร โดยส่งออกมาเป็น Binary Stream
    /// </summary>
    /// <param name="InputFilePath">ชื่อเอกสารที่ต้องการเข้ารหัส</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    /// <returns>Binary Stream ที่เข้ารหัสแล้ว</returns>
    public static byte[] EncryptStream(string InputFilePath, string SecretKey)
    {
        // read an file to new byte array
        byte[] byteArray = File.ReadAllBytes(InputFilePath);
        // write data to the new stream
        MemoryStream memoryStream = new MemoryStream(byteArray);

        return EncryptStream(memoryStream, SecretKey);
    }

    /// <summary>
    /// เข้ารหัสเอกสาร โดยส่งออกมาเป็น Binary Stream
    /// </summary>
    /// <param name="BinaryStream">Stream ที่ต้องการเข้ารหัส</param>
    /// <param name="StreamLength">ขนาดของ Stream</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    /// <returns>Binary Stream ที่เข้ารหัสแล้ว</returns>
    public static byte[] EncryptStream(Stream BinaryStream, string SecretKey)
    {
        BinaryReader BinaryRead = new BinaryReader(BinaryStream);
        byte[] binaryData = BinaryRead.ReadBytes(Convert.ToInt32(BinaryStream.Length));

        string secretKey = (SecretKey.Length == 8) ? SecretKey : MD5(SecretKey);

        //A 64 bit key and IV is required for this provider.
        //Set secret key For DES algorithm.
        DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
        DES.Key = ASCIIEncoding.ASCII.GetBytes(secretKey);
        DES.IV = ASCIIEncoding.ASCII.GetBytes(secretKey);

        //Create a DES decryptor from the DES instance.
        ICryptoTransform desencrypt = DES.CreateEncryptor();

        //Create crypto stream set to read and do a DES decryption transform on incoming bytes.
        MemoryStream memoryStream = new MemoryStream();
        CryptoStream cryptostream = new CryptoStream(memoryStream, desencrypt, CryptoStreamMode.Write);

        cryptostream.Write(binaryData, 0, binaryData.Length);
        cryptostream.FlushFinalBlock();
        cryptostream.Close();

        return memoryStream.ToArray();
    }

    /// <summary>
    /// เข้ารหัสเอกสาร
    /// </summary>
    /// <param name="InputFilePath">ชื่อเอกสารที่ต้องการเข้ารหัส</param>
    /// <param name="OutputFilePath">ชื่อเอกสารที่เข้ารหัสแล้ว</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    public static void EncryptFile(string InputFilePath, string OutputFilePath, string SecretKey)
    {
        //Create a encrypted file.
        FileStream fsEncrypted = new FileStream(OutputFilePath, FileMode.Create, FileAccess.Write);

        //Print the contents of the Encrypted file.
        byte[] byteArray = EncryptStream(InputFilePath, SecretKey);
        fsEncrypted.Write(byteArray, 0, byteArray.Length);
        fsEncrypted.Close();
    }

    /// <summary>
    /// เข้ารหัสเอกสาร
    /// </summary>
    /// <param name="BinaryStream">Stream ที่ต้องการเข้ารหัส</param>
    /// <param name="StreamLength">ขนาดของ Stream</param>
    /// <param name="OutputFilePath">ชื่อเอกสารที่เข้ารหัสแล้ว</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    public static void EncryptFile(Stream BinaryStream, string OutputFilePath, string SecretKey)
    {
        //Create a encrypted file.
        FileStream fsEncrypted = new FileStream(OutputFilePath, FileMode.Create, FileAccess.Write);

        //Print the contents of the Encrypted file.
        byte[] byteArray = EncryptStream(BinaryStream, SecretKey);
        fsEncrypted.Write(byteArray, 0, byteArray.Length);
        fsEncrypted.Close();
    }

    /// <summary>
    /// ถอดรหัสเอกสาร โดยส่งออกมาเป็น Binary Stream
    /// </summary>
    /// <param name="InputFilePath">ชื่อเอกสารที่ต้องการถอดรหัส</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    /// <returns>Binary Stream ที่ถอดรหัสแล้ว</returns>
    public static byte[] DecryptStream(string InputFilePath, string SecretKey)
    {
        // read an file to new byte array
        byte[] byteArray = File.ReadAllBytes(InputFilePath);
        // write data to the new stream
        MemoryStream memoryStream = new MemoryStream(byteArray);

        return DecryptStream(memoryStream, SecretKey);
    }

    /// <summary>
    /// ถอดรหัสเอกสาร โดยส่งออกมาเป็น Binary Stream
    /// </summary>
    /// <param name="BinaryStream">Stream ที่ต้องการถอดรหัส</param>
    /// <param name="StreamLength">ขนาดของ Stream</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    /// <returns>Binary Stream ที่ถอดรหัสแล้ว</returns>
    public static byte[] DecryptStream(Stream BinaryStream, string SecretKey)
    {
        BinaryReader BinaryRead = new BinaryReader(BinaryStream);
        byte[] binaryData = BinaryRead.ReadBytes(Convert.ToInt32(BinaryStream.Length));

        string secretKey = (SecretKey.Length == 8) ? SecretKey : MD5(SecretKey);

        //A 64 bit key and IV is required for this provider.
        //Set secret key For DES algorithm.
        DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
        DES.Key = ASCIIEncoding.ASCII.GetBytes(secretKey);
        DES.IV = ASCIIEncoding.ASCII.GetBytes(secretKey); //Set initialization vector.

        //Create a DES decryptor from the DES instance.
        ICryptoTransform desdecrypt = DES.CreateDecryptor();

        //Create crypto stream set to read and do a DES decryption transform on incoming bytes.
        MemoryStream memoryStream = new MemoryStream();
        CryptoStream cryptostreamDecr = new CryptoStream(memoryStream, desdecrypt, CryptoStreamMode.Write);

        cryptostreamDecr.Write(binaryData, 0, binaryData.Length);
        cryptostreamDecr.FlushFinalBlock();
        cryptostreamDecr.Close();

        return memoryStream.ToArray();
    }

    /// <summary>
    /// ถอดรหัสเอกสาร
    /// </summary>
    /// <param name="InputFilePath">ชื่อเอกสารที่ต้องการถอดรหัส</</param>
    /// <param name="OutputFilePath">ชื่อเอกสารที่ถอดรหัสแล้ว</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    public static void DecryptFile(string InputFilePath, string OutputFilePath, string SecretKey)
    {
        //Create a file stream to read the encrypted file back.
        FileStream fsDecrypted = new FileStream(OutputFilePath, FileMode.Create, FileAccess.Write);

        //Print the contents of the Decrypted file.
        byte[] byteArray = DecryptStream(InputFilePath, SecretKey);
        fsDecrypted.Write(byteArray, 0, byteArray.Length);
        fsDecrypted.Close();
    }

    /// <summary>
    /// ถอดรหัสเอกสาร
    /// </summary>
    /// <param name="BinaryStream">Stream ที่ต้องการถอดรหัส</param>
    /// <param name="StreamLength">ขนาดของ Stream</param>
    /// <param name="OutputFilePath">ชื่อเอกสารที่ถอดรหัสแล้ว</param>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    public static void DecryptFile(Stream BinaryStream, string OutputFilePath, string SecretKey)
    {
        //Create a file stream to read the encrypted file back.
        FileStream fsDecrypted = new FileStream(OutputFilePath, FileMode.Create, FileAccess.Write);

        //Print the contents of the Decrypted file.
        byte[] byteArray = DecryptStream(BinaryStream, SecretKey);
        fsDecrypted.Write(byteArray, 0, byteArray.Length);
        fsDecrypted.Close();
    }

    /// <summary>
    /// สร้าง 64 bits Key สำหรับเข้ารหัสและถอดรหัส
    /// </summary>
    /// <returns>64 bits Key สำหรับเข้ารหัสและถอดรหัส</returns>
    public static string GenerateKey()
    {
        // Create an instance of Symetric Algorithm. Key and IV is generated automatically.
        DESCryptoServiceProvider desCrypto = (DESCryptoServiceProvider)DESCryptoServiceProvider.Create();

        // Use the Automatically generated key for Encryption. 
        return ASCIIEncoding.ASCII.GetString(desCrypto.Key);
    }

    /// <summary>
    /// ลบข้อมูล Key ออกจากหนวยความจำ
    /// </summary>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    public static void RemoveKey(string SecretKey)
    {
        // For additional security Pin the key.
        GCHandle gch = GCHandle.Alloc(SecretKey, GCHandleType.Pinned);

        // Remove the Key from memory. 
        ZeroMemory(gch.AddrOfPinnedObject(), SecretKey.Length * 2);
        gch.Free();
    }

    /// <summary>
    /// สร้าง 64 bits Key สำหรับเข้ารหัสและถอดรหัส
    /// </summary>
    /// <param name="SecretKey">Key สำหรับเข้ารหัสและถอดรหัส</param>
    /// <returns>64 bits Key สำหรับเข้ารหัสและถอดรหัส</returns>
    private static string MD5(string SecretKey)
    {
        string strReturn = string.Empty;
        byte[] ByteSourceText = ASCIIEncoding.ASCII.GetBytes(SecretKey);

        MD5CryptoServiceProvider Md5Hash = new MD5CryptoServiceProvider();
        byte[] ByteHash = Md5Hash.ComputeHash(ByteSourceText);

        foreach (byte b in ByteHash)
            strReturn = strReturn + b.ToString("x2");

        return strReturn.Substring(0, 8);
    }

    //  Call this function to remove the key from memory after use for security
    [DllImport("KERNEL32.DLL", EntryPoint = "RtlZeroMemory")]
    private static extern bool ZeroMemory(IntPtr Destination, int Length);
}

namespace ImageGallery
{
    partial class ViewForm
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form 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.ViewPictureBox = new System.Windows.Forms.PictureBox();
            ((System.ComponentModel.ISupportInitialize)(this.ViewPictureBox)).BeginInit();
            this.SuspendLayout();
            // 
            // ViewPictureBox
            // 
            this.ViewPictureBox.Location = new System.Drawing.Point(12, 12);
            this.ViewPictureBox.Name = "ViewPictureBox";
            this.ViewPictureBox.Size = new System.Drawing.Size(268, 242);
            this.ViewPictureBox.TabIndex = 0;
            this.ViewPictureBox.TabStop = false;
            this.ViewPictureBox.Click += new System.EventHandler(this.ViewPictureBox_Click);
            // 
            // ViewForm
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(292, 266);
            this.Controls.Add(this.ViewPictureBox);
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
            this.MaximizeBox = false;
            this.MinimizeBox = false;
            this.Name = "ViewForm";
            this.Text = "View Image";
            this.Load += new System.EventHandler(this.ViewForm_Load);
            ((System.ComponentModel.ISupportInitialize)(this.ViewPictureBox)).EndInit();
            this.ResumeLayout(false);

        }

        #endregion

        private System.Windows.Forms.PictureBox ViewPictureBox;
    }
}

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;

namespace ImageGallery
{
    public partial class ViewForm : Form
    {
        private Image theImage;

        public ViewForm(Image MyImage)
        {
            InitializeComponent();

            theImage = MyImage;

            this.ClientSize = new System.Drawing.Size(theImage.Width + 24, theImage.Height + 24);
            ViewPictureBox.Size = new System.Drawing.Size(theImage.Width, theImage.Height);
        }

        private void ViewForm_Load(object sender, EventArgs e)
        {
            ViewPictureBox.Image = null;
            ViewPictureBox.SizeMode = PictureBoxSizeMode.CenterImage;
            ViewPictureBox.Image = theImage;
        }

        private void ViewPictureBox_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }
}