Question

I am updating an asp.net application and saving and retrieving documents from a mssql database. Saving was very simple but is there a way to download a file from an anchor that directly downloads from the database? Lets just say that that blob is bound within a gridview or some other data control, I would like to do this, example: <a href="<%#Eval("blobcolumn")%">Download Doc</a>. I save the file name as well.

Answer 1

You can create a Handler to download data.

sample.ashx

---

public void ProcessRequest (HttpContext context) 
{
  string id = context.Request["id"];
  if (!string.IsNullOrEmpty(id))
     {
       //read byte[] and other data from database based upon given ID
       byte []ar=//result from database
       string fileName=//filename 
       context.Response.ContentType = "Application/octet-stream";
       context.Response.AddHeader("Content-Length", ar.Length.ToString());
       context.Response.AddHeader("Content-Disposition", "attachment; filename=" +  fileName );
       context.Response.BinaryWrite(ar);
       context.Response.Flush();
       context.Response.End();
      }
}

and request via hyperlinks

<a href="sample.ashx?id=101">Download .zip</a>
<a href='sample.ashx?id=<%#Eval("ID")%>'><%#Eval("Desc")%></a>