ASP.NET / Sparx Systems Enterprise Architect : Read binary Image from Database ( BLOB ) and show / display it on a webpage

Problem

A binary picture that has been saved in a database or an Access File (i.e. of the Sparx Systems Enterprise Architect) shall be displayed on a web page.

Approach

  1. Create a new ASP.NET Webform and name it GetImage.aspx
  2. Go to the Page_Load function in it
  3. Paste the code under solution in the area in customize according your data structure (here it is Sparx EA).
  4. Create a img-Tag in HTML, that has a src-Attribute pointing to that webpage with a get parameter img={your image id}
  5. Use Response.BinaryWrite in the way shown below

Solution

using System;
using System.Collections.Generic;
using System.Data.OleDb;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class GetImage : System.Web.UI.Page
{
    // Mit folgender URL Kann ein Bild nun rausgeladen werden 
    // http://localhost:51241/GetImage.aspx?img=343868582
    // und entsprechend in HTML über den Image-Tag geladen werden:
    // <img src="GetImage.aspx?img=343868582" />
    protected void Page_Load(object sender, EventArgs e)
    {
        string sqlStatement = @"
            SELECT Image 
            FROM t_image 
            WHERE ImageID={ImageID}         
        ";

        sqlStatement = sqlStatement.Replace("{ImageID}", Request.QueryString["img"].Trim());

        OleDbConnection conn = new OleDbConnection(MyConfigurationManager.eapFilePath);

        try
        {
            conn.Open();
            OleDbCommand comm = new OleDbCommand();
            comm.Connection = conn;
            comm.CommandText = sqlStatement;

            OleDbDataReader reader = comm.ExecuteReader();

            while (reader.Read())
            {
                Response.ContentType = "image/jpeg"; // if your image is a jpeg of course
                Response.BinaryWrite((byte[])reader.GetValue(0));
            }
        }
        catch (Exception ex)
        {
            //return e.Message;
        }
        finally
        {
            conn.Close();
        }
    }
}

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