Inserting & retrieving images from SQL Server database using stored procedures

Prashanth Chindam
May 31
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Article

Objective

To insert & retrieve images from SQL server database using stored procedures and also to perform insert, search, update, and delete operations & navigation of records.

Introduction

As we want to insert images into the database using stored procedures, we have to create a table and stored procedures in the database.

Query for creating a table in our application.

CREATE TABLE student (
    sno INT PRIMARY KEY,
    sname VARCHAR(50),
    course VARCHAR(50),
    fee MONEY,
    photo IMAGE
)

Stored procedures

create procedure get_student
as
select sno, sname, course, fee, photo from student
-- -- -- -- -- -- -
create procedure insert_student(@sno int, @sname varchar(50), @course varchar(50), @fee smallmoney, @photo image = null)
as
insert into student(sno, sname, course, fee, photo) values(@sno, @sname, @course, @fee, @photo)
    -- -- -- -- -- -- -- -- -- -- -
    create procedure update_student(@sno int, @sname varchar(50), @course varchar(50), @fee smallmoney, @photo image = null)
as
update student set sname = @sname, course = @course, fee = @fee, photo = @photo where sno = @sno
    -- -- -- -- -- -- -- --
create procedure delete_student(@sno int = null)
as
if not(@sno = null)
delete from student where sno = @sno
    -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

Design

Design the form as above with 1 PictureBox control, 1 OpenFileDialog control, 4 Labels, 4 TextBoxes, and 11 Buttons.

PictureBox1 Properties

BorderStyle=Fixed3D; SizeMode=StretchImage

Note that OpenFileDialog control appears below the form (not on the form).

Introduction to code

In order to communicate with the SQL server database, including the namespace using System.Data.SqlClient.

In this application, we will search for a record by taking input from the InputBox. For this, we have to add a reference to Microsoft.VisualBasic.

Adding a Reference to 'Microsoft.VisualBasic'

Goto Project Menu ->Add Reference -> select 'Microsoft.VisualBasic' from the .NET tab.

In order to use this reference, we have to include the namespace, 'using Microsoft.VisualBasic' in the code.

Converting an image into binary data

We can't store an image directly into the database. For this, we have two solutions.

To store the location of the image in the database
Convert the image into binary data insert that binary data into the database and convert that back to the image when retrieving the records.

If we store the location of an image in the database and suppose that image is deleted or moved from that location, we will face problems while retrieving the records. So it is better to convert an image into binary data and insert that binary data into the database and convert that back to an image while retrieving records.

We can convert an image into binary data using 1. FileStream (or) 2. MemoryStream

1. FileStream uses file location to convert an image into binary data which we may/may not provide when updating a record.

Ex

FileStream fs = new FileStream(openFileDialog1.FileName, FileMode.Open, FileAccess.Read);
byte[] photo_aray = new byte[fs.Length];
fs.Read(photo_aray, 0, photo_aray.Length);

2. So it is better to use MemoryStream which uses the image in the PictureBox to convert an image into binary data.

Ex

MemoryStream ms = new MemoryStream();
pictureBox1.Image.Save(ms, ImageFormat.Jpeg);
byte[] photo_aray = new byte[ms.Length];
ms.Position = 0;
ms.Read(photo_aray, 0, photo_aray.Length);

In order to use FileStream or MemoryStream we have to include the namespace: 'using System.IO'.

OpenFileDialog Control

We use OpenFileDialog control to browse for the images (photos) to insert into the record.

Using DataAdapter with StoredProcedures

We can use the command object to work with stored procedures bypassing the stored procedure name to the command object and specifying CommandType as StoredProcedure.

Ex

cmd = new SqlCommand("get_student", con);
cmd.CommandType = CommandType.StoredProcedure;

DataAdapter can't interact directly with the stored procedures, but if we need to use DataAdapter while working with stored procedures, we can achieve this by passing the command object to the DataAdapter.

Loading the constraint details into the dataTable

In this app., we use the Find() method to search a record, which requires details of a primary-key column, which can be provided using the statement.

adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;

Pointing to the current record in Table

After searching for a record, we have to get the index of that record so that we can show the next and previous records when we press the'>>'(next) and '<<'(previous) buttons.

Ex

rno = ds.Tables[0].Rows.IndexOf(drow);

Code

using System;
using System.Windows.Forms;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using Microsoft.VisualBasic;

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

        SqlConnection con;
        SqlCommand cmd;
        SqlDataAdapter adapter;
        DataSet ds;
        int rno = 0;
        MemoryStream ms;
        byte[] photo_aray;

        private void Form1_Load(object sender, EventArgs e)
        {
            con = new SqlConnection("user id=sa;password=123;database=prash");
            loaddata();
            showdata();
        }

        void loaddata()
        {
            cmd = new SqlCommand("get_student", con);
            cmd.CommandType = CommandType.StoredProcedure;
            adapter = new SqlDataAdapter(cmd);
            adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;
            ds = new DataSet();
            adapter.Fill(ds, "student");
        }

        void showdata()
        {
            if (ds.Tables[0].Rows.Count > 0)
            {
                textBox1.Text = ds.Tables[0].Rows[rno][0].ToString();
                textBox2.Text = ds.Tables[0].Rows[rno][1].ToString();
                textBox3.Text = ds.Tables[0].Rows[rno][2].ToString();
                textBox4.Text = ds.Tables[0].Rows[rno][3].ToString();
                pictureBox1.Image = null;
                if (ds.Tables[0].Rows[rno][4] != System.DBNull.Value)
                {
                    photo_aray = (byte[])ds.Tables[0].Rows[rno][4];
                    MemoryStream ms = new MemoryStream(photo_aray);
                    pictureBox1.Image = Image.FromStream(ms);
                }
            }
            else
                MessageBox.Show("No Records");
        }

        private void browse_Click(object sender, EventArgs e)
        {
            openFileDialog1.Filter = "jpeg|*.jpg|bmp|*.bmp|all files|*.*";
            DialogResult res = openFileDialog1.ShowDialog();
            if (res == DialogResult.OK)
            {
                pictureBox1.Image = Image.FromFile(openFileDialog1.FileName);
            }
        }

        private void clear_Click(object sender, EventArgs e)
        {
            textBox1.Text = textBox2.Text = textBox3.Text = textBox4.Text = "";
            pictureBox1.Image = null;
        }

        private void insert_Click(object sender, EventArgs e)
        {
            cmd = new SqlCommand("insert_student", con);
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddWithValue("@sno", textBox1.Text);
            cmd.Parameters.AddWithValue("@sname", textBox2.Text);
            cmd.Parameters.AddWithValue("@course", textBox3.Text);
            cmd.Parameters.AddWithValue("@fee", textBox4.Text);
            conv_photo();
            con.Open();
            int n = cmd.ExecuteNonQuery();
            con.Close();
            if (n > 0)
            {
                MessageBox.Show("record inserted");
                loaddata();
            }
            else
                MessageBox.Show("insertion failed");
        }

        void conv_photo()
        {
            //converting photo to binary data
            if (pictureBox1.Image != null)
            {
                ms = new MemoryStream();
                pictureBox1.Image.Save(ms, ImageFormat.Jpeg);
                byte[] photo_aray = new byte[ms.Length];
                ms.Position = 0;
                ms.Read(photo_aray, 0, photo_aray.Length);
                cmd.Parameters.AddWithValue("@photo", photo_aray);
            }
        }

        private void search_Click(object sender, EventArgs e)
        {
            try
            {
                int n = Convert.ToInt32(Interaction.InputBox("Enter sno:", "Search", "20", 100, 100));
                DataRow drow;
                drow = ds.Tables[0].Rows.Find(n);
                if (drow != null)
                {
                    rno = ds.Tables[0].Rows.IndexOf(drow);
                    textBox1.Text = drow[0].ToString();
                    textBox2.Text = drow[1].ToString();
                    textBox3.Text = drow[2].ToString();
                    textBox4.Text = drow[3].ToString();
                    pictureBox1.Image = null;
                    if (drow[4] != System.DBNull.Value)
                    {
                        photo_aray = (byte[])drow[4];
                        MemoryStream ms = new MemoryStream(photo_aray);
                        pictureBox1.Image = Image.FromStream(ms);
                    }
                }
                else
                    MessageBox.Show("Record Not Found");
            }
            catch
            {
                MessageBox.Show("Invalid Input");
            }
        }

        private void update_Click(object sender, EventArgs e)
        {
            cmd = new SqlCommand("update_student", con);
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddWithValue("@sno", textBox1.Text);
            cmd.Parameters.AddWithValue("@sname", textBox2.Text);
            cmd.Parameters.AddWithValue("@course", textBox3.Text);
            cmd.Parameters.AddWithValue("@fee", textBox4.Text);
            conv_photo();
            con.Open();
            int n = cmd.ExecuteNonQuery();
            con.Close();
            if (n > 0)
            {
                MessageBox.Show("Record Updated");
                loaddata();
            }
            else
                MessageBox.Show("