в 15:31, 26 мая 2010

2010-05-26T15:31:53Z

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2010-05-26T12:19:14Z

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==Display image==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.ruponentModel;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data;
using System.Data.SqlClient;
using System.IO;
public class DisplayImages : Form
{
public DisplayImages()
{
InitializeComponent();
images = new Images();
if (images.GetRow())
{
this.textBox1.Text = images.GetFilename();
this.pictureBox1.Image = (Image)images.GetImage();
}
else
{
this.textBox1.Text = "DONE";
this.pictureBox1.Image = null;
}
}
private void button1_Click(object sender, EventArgs e)
{
if (images.GetRow())
{
this.textBox1.Text = images.GetFilename();
this.pictureBox1.Image = (Image)images.GetImage();
}
else
{
this.textBox1.Text = "DONE";
this.pictureBox1.Image = null;
}
}
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.textBox1 = new System.Windows.Forms.TextBox();
this.pictureBox1 = new System.Windows.Forms.PictureBox();
((System.ruponentModel.ISupportInitialize)(this.pictureBox1)).BeginInit();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(175, 22);
this.button1.Name = "button1";
this.button1.Size = new System.Drawing.Size(75, 23);
this.button1.TabIndex = 0;
this.button1.Text = "Show Image";
this.button1.UseVisualStyleBackColor = true;
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// textBox1
//
this.textBox1.Location = new System.Drawing.Point(30, 22);
this.textBox1.Name = "textBox1";
this.textBox1.Size = new System.Drawing.Size(126, 20);
this.textBox1.TabIndex = 1;
//
// pictureBox1
//
this.pictureBox1.Location = new System.Drawing.Point(30, 64);
this.pictureBox1.Name = "pictureBox1";
this.pictureBox1.Size = new System.Drawing.Size(220, 221);
this.pictureBox1.TabIndex = 2;
this.pictureBox1.TabStop = false;
//
// DisplayImages
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(292, 297);
this.Controls.Add(this.pictureBox1);
this.Controls.Add(this.textBox1);
this.Controls.Add(this.button1);
this.Name = "DisplayImages";
this.Text = "Display Images";
((System.ruponentModel.ISupportInitialize)(this.pictureBox1)).EndInit();
this.ResumeLayout(false);
this.PerformLayout();
}
private System.Windows.Forms.Button button1;
private System.Windows.Forms.TextBox textBox1;
private System.Windows.Forms.PictureBox pictureBox1;
private Images images;

[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new DisplayImages());
}
}
public class Images
{
string imageFilename = null;
byte[] imageBytes = null;
SqlConnection imageConnection = null;
SqlCommand imageCommand = null;
SqlDataReader imageReader = null;
// Constructor
public Images()
{
imageConnection = new SqlConnection(@"data source = .\sqlexpress;integrated security = true;initial catalog = tempdb;");
imageCommand = new SqlCommand(@"select imagefile,imagedata from imagetable ", imageConnection);
imageConnection.Open();
imageReader = imageCommand.ExecuteReader();
}
public Bitmap GetImage()
{
MemoryStream ms = new MemoryStream(imageBytes);
Bitmap bmap = new Bitmap(ms);
return bmap;
}
public string GetFilename()
{
return imageFilename;
}
public bool GetRow()
{
if (imageReader.Read())
{
imageFilename = (string)imageReader.GetValue(0);
imageBytes = (byte[])imageReader.GetValue(1);
return true;
}
else
{
return false;
}
}
public void EndImages()
{
imageReader.Close();
imageConnection.Close();
}
}</source>

==LoadImages.cs==

<source lang="csharp">using System;
using System.Data;
using System.Data.SqlClient;
using System.IO;
class LoadImages
{
static void Main()
{
string imageFileLocation ="C:\\";
string imageFilePrefix = "a";
int numberImageFiles = 1;
string imageFileType = ".jpg";
int maxImageSize = 10000;
SqlConnection conn = null;
SqlCommand cmd = null;
conn = new SqlConnection(@"server = .\sqlexpress;integrated security = true;database = tempdb");
conn.Open();
cmd = new SqlCommand();
cmd.Connection = conn;

cmd.rumandText = @"create table imagetable(imagefile nvarchar(20),imagedata varbinary(max))";
cmd.ExecuteNonQuery();
cmd.rumandText = @"insert into imagetable values (@imagefile, @imagedata)";
cmd.Parameters.Add("@imagefile", SqlDbType.NVarChar, 20);
cmd.Parameters.Add("@imagedata", SqlDbType.Image, 1000000);
cmd.Prepare();
string imageFileName = null;
byte[] imageImageData = null;
imageFileName = imageFilePrefix + imageFileType;
imageImageData = LoadImageFile(imageFileName, imageFileLocation, maxImageSize);
cmd.Parameters["@imagefile"].Value = imageFileName;
cmd.Parameters["@imagedata"].Value = imageImageData;

cmd.rumandText = cmd.rumandText;
cmd.ExecuteNonQuery();
}
static byte[] LoadImageFile(string fileName,string fileLocation,int maxImageSize)
{
byte[] imagebytes = null;
string fullpath = fileLocation + fileName;
Console.WriteLine("Loading File:");
Console.WriteLine(fullpath);
FileStream fs = new FileStream(fullpath, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fs);
imagebytes = br.ReadBytes(maxImageSize);
Console.WriteLine("Imagebytes has length {0} bytes.",imagebytes.GetLength(0));
return imagebytes;
}
}</source>

==Load image to database==

<source lang="csharp">/*
Quote from

Beginning C# 2005 Databases From Novice to Professional
# Paperback: 528 pages
# Publisher: Apress (December 18, 2006)
# Language: English
# ISBN-10: 159059777X
# ISBN-13: 978-1590597774
*/

using System;
using System.Data;
using System.Data.SqlClient;
using System.IO;
namespace LoadImages
{
class LoadImages
{
string imageFileLocation =@"Images\";
string imageFilePrefix = "milk";
int numberImageFiles = 8;
string imageFileType = ".gif";
int maxImageSize = 10000;
SqlConnection conn = null;
SqlCommand cmd = null;
static void Main()
{
LoadImages loader = new LoadImages();
try
{
// Open connection
loader.OpenConnection();
// Create command
loader.CreateCommand();
// Create table
loader.CreateImageTable();
// Prepare insert
loader.PrepareInsertImages();
// Insert images
int i;
for (i = 1; i <= loader.numberImageFiles; i++)
{
loader.ExecuteInsertImages(i);
}
}
catch (SqlException ex)
{
Console.WriteLine(ex.ToString());
}
finally
{
loader.CloseConnection();
}
}
void OpenConnection()
{
// Create connection
conn = new SqlConnection(@"server = .\sqlexpress;integrated security = true;database = tempdb");
// Open connection
conn.Open();
}
void CloseConnection()
{
conn.Close();
Console.WriteLine("Connection Closed.");
}
void CreateCommand()
{
cmd = new SqlCommand();
cmd.Connection = conn;
}
void ExecuteCommand(string cmdText)
{
int cmdResult;
cmd.rumandText = cmdText;
Console.WriteLine("Executing command:");
Console.WriteLine(cmd.rumandText);
cmdResult = cmd.ExecuteNonQuery();
Console.WriteLine("ExecuteNonQuery returns {0}.", cmdResult);
}
void CreateImageTable()
{
ExecuteCommand(@"create table imagetable(
imagefile nvarchar(20),
imagedata varbinary(max))");
}
void PrepareInsertImages()
{
cmd.rumandText = @"insert into imagetable values (@imagefile, @imagedata)";
cmd.Parameters.Add("@imagefile", SqlDbType.NVarChar, 20);
cmd.Parameters.Add("@imagedata", SqlDbType.Image, 1000000);
cmd.Prepare();
}
void ExecuteInsertImages(int imageFileNumber)
{
string imageFileName = null;
byte[] imageImageData = null;
imageFileName =imageFilePrefix + imageFileNumber.ToString() + imageFileType;
imageImageData =LoadImageFile(imageFileName, imageFileLocation, maxImageSize);
cmd.Parameters["@imagefile"].Value = imageFileName;
cmd.Parameters["@imagedata"].Value = imageImageData;
ExecuteCommand(cmd.rumandText);
}
byte[] LoadImageFile(string fileName,string fileLocation,int maxImageSize)
{
byte[] imagebytes = null;
string fullpath = fileLocation + fileName;
Console.WriteLine("Loading File:");
Console.WriteLine(fullpath);
FileStream fs = new FileStream(fullpath, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fs);
imagebytes = br.ReadBytes(maxImageSize);
Console.WriteLine("Imagebytes has length {0} bytes.",imagebytes.GetLength(0));
return imagebytes;
}
}
}</source>

==Read Bitmap from database==

<source lang="csharp">using System;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.IO;
public class MainClass
{
public static void Main()
{
SqlConnection imageConnection = new SqlConnection(@"data source = .\sqlexpress;integrated security = true;initial catalog = tempdb;");
SqlCommand imageCommand = new SqlCommand(@"select imagefile,imagedata from imagetable ",imageConnection);
imageConnection.Open();
SqlDataReader imageReader = imageCommand.ExecuteReader();
string imageFilename = (string) imageReader.GetValue(0);
byte[] imageBytes = (byte[]) imageReader.GetValue(1);
MemoryStream ms = new MemoryStream(imageBytes);
Bitmap bmap = new Bitmap(ms);
imageReader.Close();
imageConnection.Close();
}
}</source>

==Writes binary data to a file==

<source lang="csharp">using System;
using System.Data.SqlClient;
using System.Data;
using System.IO;
public class ConnectionTest
{
private static string connectionString = "Data Source=localhost;Initial Catalog=pubs;Integrated Security=SSPI";
private static string SQL = "SELECT pub_id, logo FROM pub_info";
public static void Main()
{
int bufferSize = 100;
byte[] bytes = new byte[bufferSize];
long bytesRead;
long readFrom;
SqlConnection con = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(SQL, con);
con.Open();
SqlDataReader r = cmd.ExecuteReader(CommandBehavior.SequentialAccess);
while (r.Read())
{
string filename = "logo.bmp";
FileStream fs = new FileStream(filename, FileMode.OpenOrCreate, FileAccess.Write);
BinaryWriter bw = new BinaryWriter(fs);
readFrom = 0;
do {
bytesRead = r.GetBytes(1, readFrom, bytes, 0, bufferSize);
bw.Write(bytes);
bw.Flush();
readFrom += bufferSize;
} while (bytesRead == bufferSize);
bw.Flush();
bw.Close();
fs.Close();
}
r.Close();
con.Close();
}
}</source>

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в 15:31, 26 мая 2010

Admin: 1 версия