Question

I am trying to open the PDF on clicking a link in browser. It is actually from DB as BLOB. But i am getting Error : file does not begin with ‘ pdf-‘ asp.net

This is the code i am using,

        if (dt.Rows.Count > 0)

        {

            string strExtenstion = dt.Rows[0]["DGN0101FILE_EXTENSION"].ToString();

            byte[] bytFile = (byte[])dt.Rows[0]["DGN0101FILE"];

            string fileName = dt.Rows[0]["DGN0101FILE_NAME"].ToString();

            Response.Clear();

            Response.ClearContent();

            Response.ClearHeaders();

            Response.Buffer = true;

            if (strExtenstion == ".doc" || strExtenstion == ".docx")
            {
                Response.ContentType = "application/vnd.ms-word";
            }
            else if (strExtenstion == ".xls" || strExtenstion == ".xlsx")
            {
                Response.ContentType = "application/vnd.ms-excel";
            }
            else if (strExtenstion == ".pdf")
            {
                Response.ContentType = "application/pdf";
            } 
            Response.AddHeader("Content-Length", bytFile.Length.ToString());
            Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName);
            Response.BinaryWrite(bytFile); 
            Response.Flush();
            Response.End();
            Response.Clear();
        }

Answer 1

A valid PDF file starts with %PDF-1.5 or similar. My guess is that your data is not being stored or retrieved properly.

• View the original file in Acrobat/Acrobat Reader to ensure it’s actually a PDF.
• View the original file in a text editor and visually inspect it.
• Check the database table to ensure that there is binary data in the row.
• Check the length of the byte array being extracted from the database.