Here is the code.

I don't know how to attach the pdf file that is generated.
The error is being thrown by adobe reader.\

It states : adobe reader could not open 'test[1].pdf' because it is either not supported file type or because the file has been damaged (for example it was sent as an email attachment and wasn't correctly decoded).

in page_load 

string name = "test.pdf";
            FileStream fs = new FileStream ( Server.MapPath("~/") + name, FileMode.Create, FileAccess.Write );
            StreamWriter sw = new StreamWriter ( fs, System.Text.Encoding.GetEncoding ( "gb2312" ) );
            sw.WriteLine ( "Hello World" );
            sw.Close ( );


            // If inside of a page:


            Response.AddHeader ( "Content-Disposition", "attachment; filename=" + Server.UrlEncode ( name ) );
            Response.ContentType = "application/pdf";
            //Response.AddHeader ( "Content-Type", "binary/octet-stream" );
            //Response.AddHeader ( "Content-Disposition", "attachment; filename=" + downloadName + "; size=" + downloadBytes.Length.ToString ( ) );
            //Response.Flush ( );
            //Response.BinaryWrite ( downloadBytes ); 
            Response.Flush ( );
            Response.End ( );


            Response.WriteFile ( name );
            Response.End ( );