Extracting blob data and binding to datagrid asp.net 1.1 vb.net

Experts, I am trying to bind blob's do a datagrid which I have never done in asp.net 1.1.  We have a database table that stores pdf's, docs, and gif's as blobs.  How do I extract blob's and bind it to a datagrid?
What I would like to do in the datagrid is have a hyper link column that when clicked displays the blob in its format as doc, pdf, gif etc.  Any ideas?
tentavariousAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

jasco4617Commented:
Tentavarious,

You would need to have a page, lets call it download.aspx and pass it a document ID that would be the the primary key for the column that has the stored blob data.

you would then need to have a query that pulls that information from the database and use that data to modify the http header for the request and stream the blob data.  See the below example.

--------
        Byte[] content = new Byte[0];
        String filename = "";
        String contentType = "";

        Response.ContentType = contentType;
        Response.AddHeader("Content-Disposition", "attachment; filename=" + filename);
        Response.BinaryWrite(content);
        Response.End();
-------

You would set the appriate variable information from what was returned in your query.   for this to work correctly, you must have the contentType (mime type) or else the browser will not know how to work with the data.

I hope this answers your question and points you in the right direction.

- pat
0
tentavariousAuthor Commented:
i was actually looking for maybe and example of using a datareader or dataset to read in the blob column.  Is there something special I need to do?
0
jasco4617Commented:
Here is an example from .net 2.0....i am not sure if this is the same with 1.1 or not though (i think it is, give it a shot):




protected void Page_Load(object sender, EventArgs e)
    {
        String doc = Request.QueryString["doc"];
        try
        {
            Int32.Parse(doc);
        }
        catch
        {
            Response.Redirect("Default.aspx");
        }

        SqlConnection conn = new SqlConnection(WebConfigurationManager.ConnectionStrings["SQLConnString"].ConnectionString);
        SqlCommand cmd = new SqlCommand("SELECT files.*, fileTypes.* FROM files INNER JOIN fileTypes ON files.typeID = fileTypes.typeID WHERE fileID=@fileID", conn);
        cmd.Parameters.Add("@fileID", SqlDbType.Int).Value = doc;
        cmd.Connection.Open();
        SqlDataReader reader = cmd.ExecuteReader();
        Byte[] content = new Byte[0];
        String filename = "";
        String contentType = "";
        if (reader.HasRows)
        {
            while (reader.Read())
            {
                contentType = reader.GetValue(6).ToString();

                //content = new Byte[reader.GetInt32(7)];
                content = reader.GetSqlBytes(5).Buffer;
                //reader.GetBytes(5, 0, content, 0, reader.GetInt32(7));
                filename = reader.GetValue(1).ToString();
            }
        }

        cmd.Connection.Close();

        Response.ContentType = contentType;
        Response.AddHeader("Content-Disposition", "attachment; filename=" + filename);
        Response.BinaryWrite(content);
        Response.End();
    }
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
ASP.NET

From novice to tech pro — start learning today.