C # access to one of the SQL Server databases: binary access picture files

Create a project

1. Add a table named rwtest to the SQL Server MYTest database. The table field is set as follows:

A. uniquely identifies the field name is "ID"and the type is Int.

B. a field of type VarChar called "Description" with a field length of

c. a field of type Image called "Imgfield" .

2. start visual Studio. NET and create a new Visual C # Window S Application project.

3. Drag two Button controls from the toolbar to the default form, Form1 .

4.        in the Properties window, modify name to buttonfiletodb , text properties are saved from file to database , then modify name to buttondbtofile , text The property is saved from the database to the file .

5 Place 2 TextBox and 1 PictureBox from the toolbar Controls:theName property is:textboxgetid, textboxgetdescription, picture Boxgetimage , showing IDs read from the database ,Description,Imgfield fields.

SOURCE Example

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

using System.Data.SqlClient;

using System.IO;

using System.Collections;

// Database Description: MyTest database, rwtest Table , contains 3 columns: ID (int), Description (varchar), Imgfield (Image)

namespace rwimgsql

{

public partial class Form1 : Form

    {

public Form1 ()

        {

InitializeComponent ();

        }

private void Buttonfiletodb_click (object sender, EventArgs e)

        {

SqlConnection sqlconnection = new SqlConnection ("Data Source = Liuxueqin; Initial catalog=mytest;integrated security=true ");

SqlDataAdapter sqldataadapter = New SqlDataAdapter ( > "SELECT * from Rwtest", SqlConnection);

sqlcommandbuilder sqlcommandbuilder = new SqlCommandBuilder(SqlDataAdapter );

DataSet DataSet = new DataSet("rwtest");

sqldataadapter.missingschemaaction = MissingSchemaAction. AddWithKey; // Identify existing DataSet the action to perform if the schema does not match the incoming data.

String currentexename = system.diagnostics. Process. GetCurrentProcess (). Mainmodule.filename;

String imagefile = System.IO. Path. GetDirectoryName (currentexename) + "\f1.jpg";

System.IO. FileStream FileStream = new FileStream(imagefile, FileMode. OpenOrCreate, fileaccess. ReadWrite);

byte [] myData = new byte [filestream.length];

filestream.read (myData, 0, System. Convert. ToInt32 (filestream.length)); // reads a block of bytes from the stream and writes the data to the buffer

filestream.close ();

try

            {

Sqldataadapter.fill (DataSet, "Rwtest");

//datarow represents a row of data in a DataTable

System.Data. DataRow DataRow;

dataRow = dataset.tables["Rwtest"]. NewRow ();

datarow1["ID"] = 1;

datarow1["Description"] = "This would is Description text";

datarow1["Imgfield"] = MyData;

dataset.tables["Rwtest"]. Rows.Add (DataRow);

sqldataadapter.update (DataSet, "Rwtest");

sqlconnection.close ();

MessageBox. Show (" write to database success!") ", " Information tips , messageboxbuttons. OK, MessageBoxIcon. Information);

            }

Catch (Exception ex)

            {

If (sqlconnection.state = = ConnectionState. Open)

                {

sqlconnection.close ();

                }

MessageBox. Show ( Write database failed )+ex. Message, " informational hint ", messageboxbuttons. OK, MessageBoxIcon. ERROR);

            }

        }

private void Buttondbtofile_click (object sender, EventArgs E

        {

SqlConnection SqlConnection = new SqlConnection("Data Source=liuxueqin ; Initial catalog=mytest;integrated security=true ");

SqlDataAdapter SqlDataAdapter = new SqlDataAdapter("SELECT * From Rwtest ", SqlConnection);

sqlcommandbuilder sqlcommandbuilder = new SqlCommandBuilder(SqlDataAdapter );

DataSet DataSet = new DataSet("rwtest");

byte[] MyData = new byte[0];

Sqldataadapter.fill (DataSet, "Rwtest");

DataRow myrow;

myrow = dataset.tables["Rwtest"]. Rows[0];

MyData = (byte[]) myrow["Imgfield"];

int arraysize = mydata.getupperbound (0);

String currentexename = system.diagnostics. Process. GetCurrentProcess (). Mainmodule.filename;

string imagefile = System.IO. Path. GetDirectoryName (currentexename) + "\f2.jpg";

FileStream fs = new FileStream(imagefile, FileMode. OpenOrCreate, fileaccess. Write);

FS. Write (MyData, 0, arraysize);

FS. Close ();

//--- 2 textBox and 1 on the interface PictureBox that is used to display the data read from the database. ID , Description , ImageField Field

textboxgetid.text = myrow["ID"]. ToString ();

textboxgetdescription.text = myrow["Description"]. ToString ();

pictureboxgetimage.image = Image. FromFile (ImageFile);

if (sqlconnection.state = = connectionstate. Open)

            {

sqlconnection.close ();

            }

MessageBox. Show (" read data from database success!") ", " Information tips , messageboxbuttons. OK, MessageBoxIcon. Information);

        }

}

}

 

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