Retrive a Image from SQL using web service in c#.

/* Here is the SQL Table structure and procedure for reference.

create database test_Imagedb
use test_Imagedb


create table image_tbl(imgname varchar(100), my_image image)

alter procedure Insert_Image (
    @image_name varchar(100),
    @picture image)
as
begin
insert into image_tbl values(@image_name,@picture)
end

create procedure Get_Image_Name
as
begin
select * from image_tbl
end

create procedure Get_Image(@image_name varchar(100))
as
begin
select * from image_tbl where imgname=@image_name
end   

*/



using System;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.IO;
using System.Data.SqlClient;
using System.Data;


[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]


public class Service : System.Web.Services.WebService
{
    DataSet ds;
    SqlCommand cmd;
    SqlConnection conn;
    SqlDataAdapter sda;
    string connstr = @"Data Source=kannan;Initial Catalog=test_Imagedb;Persist Security Info=True;User ID=sa;Password=cgvak123";
 

    public Service () {
                
        //Uncomment the following line if using designed components
        //InitializeComponent();
    }

    [WebMethod]
    public string HelloWorld() {
        return "Hello World";
    }

    /*
     * Web Method Name  :   Retrive_Image_Name
     * Description      :   This method is used to retrive the image name, image from the data table,
     *                      the value from the table is returned in dataset.
     * StoredProcedure  :   Get_Image_Name
     * Return Type      :   DataSet
     *
     * */
    [WebMethod]
    public DataSet Retrive_Image_Name()
    {
        try
        {           
            conn = new SqlConnection(connstr);
            conn.Open();
            ds = new DataSet();
            cmd = new SqlCommand("Get_Image_Name", conn);
            cmd.CommandType = CommandType.StoredProcedure;
            sda = new SqlDataAdapter(cmd);
            sda.Fill(ds);          
            return ds;
        }
        catch (Exception ex)
        {
            throw ex;
        }
        finally
        {
            cmd.Dispose();
            conn.Close();
            conn.Dispose();
        }
            
    }

    /*
    * Web Method Name  :   Retrive_Image
    * Description      :   This method is used to retrive the image from the data table according to the Image Name.    
    *                      Actually the image is converted in to bytes and image is returned in the form of bytes.
    * StoredProcedure  :   Get_Image
    * Return Type      :   Byte Array
    *
    * */
    [WebMethod]
    public byte[] Retrive_Image(string simagename)
    {
        try
        {            
            conn = new SqlConnection(connstr);
            conn.Open();
            ds = new DataSet();
             cmd = new SqlCommand("Get_Image", conn);
            cmd.Parameters.Add("image_name", SqlDbType.VarChar, 100).Value = simagename;
            cmd.CommandType = CommandType.StoredProcedure;
            SqlDataReader sdr;
            sdr = cmd.ExecuteReader();
            byte[] file = null;
            while (sdr.Read())
            {
                file = (byte[])sdr["my_image"];
            }
            sdr.Close();

            
            MemoryStream memoryStream = new MemoryStream();
            memoryStream.Write(file, 0, file.Length);

            Context.Response.Buffer = true;
            Context.Response.BinaryWrite(file);

            memoryStream.Dispose();
            return file;
        }
        catch (Exception ex)
        {
            throw ex;
        }
        finally
        {
            cmd.Dispose();
            conn.Close();
            conn.Dispose();
        }
    }


    /*
    * Web Method Name  :   updateImagedata
    * Description      :   This method is used to upload the image name and image in to the table.
    *                      Image name and the image is passed as argument.
    * StoredProcedure  :   Get_Image
    * Return Type      :   Void
    *
    * */

    [WebMethod]
    public void updateImagedata(string sPicName, byte[] data)
    {
        string imagename = sPicName;
        try
        {
            if (imagename != "")
            {
                conn = new SqlConnection(connstr);
                conn.Open();
                cmd = new SqlCommand("Insert_Image", conn);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.Add("image_name", SqlDbType.VarChar, 100).Value = imagename;
                cmd.Parameters.Add("picture", SqlDbType.Image).Value = data;
                cmd.ExecuteNonQuery();
            }
        }
        catch (Exception ex)
        {
            throw ex;
        }
        finally
        {
            cmd.Dispose();
            conn.Close();
            conn.Dispose();
        }
    }

}

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