Add DateTime based on a value from DropDownList

Hello Experts,

I have a web form that I need help with. I would like to be able to add the current DateTime to a field in my DB if a DropDownList value is selected as "Closed". If the value from the DropDownList value is NOT "Closed" then do not add DateTime to field in DB.

Please see my current CodeBehind below. There is no TextBox for the Completion Date. I somehow need to programatically put that value into my DB basd on the value from the DropDownList if it's "Closed".

CodeBehind:

protected void btnModifyTicket_Click(object sender, EventArgs e)
    {
        int TicketID = Convert.ToInt32(Request.QueryString["tkt_id"].ToString());

        if (Page.IsValid) // make sure all fields have data before Inserting to DB.
        {
            if (fuAttachFile.HasFile)  // a file has been uploaded
            {
                //Make sure we are dealing a .pdf file only
                string extension = Path.GetExtension(fuAttachFile.PostedFile.FileName).ToLower();
                string MIMEType = null;

                switch (extension)
                {
                    case ".pdf":
                        MIMEType = "application/pdf";
                        break;
                    case ".doc":
                        MIMEType = "application/msword";
                        break;
                    case ".xls":
                        MIMEType = "application/vnd.ms-excel";
                        break;
                    case ".txt":
                        MIMEType = "text/plain";
                        break;
                    case ".png":
                        MIMEType = "image/png";
                        break;
                    case ".jpg":
                        MIMEType = "image/jpeg";
                        break;
                    case ".jpeg":
                        MIMEType = "image/jpeg";
                        break;
                    case ".vsd":
                        MIMEType = "application/vnd.visio";
                        break;
                    default:
                        lblFileTypeError.Visible = true;
                        lblFileTypeError.Text = "PDF files only.";
                        return;
                }

                string filename = fuAttachFile.PostedFile.FileName.Split(new char[] { '\\' }).Last();
                int fileSize = fuAttachFile.PostedFile.ContentLength;

                // Allow only files less than 1,048,576 bytes (approximately 1 MB) to be uploaded.
                if ((fileSize < 1048576))
                {
                    SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["CMDB"].ConnectionString);

                    SqlCommand cmd = new SqlCommand();
                    cmd.CommandText = "ModifyTicket";
                    cmd.CommandType = CommandType.StoredProcedure;
                    cmd.Connection = conn;

                    // Load PDF InputStream into Byte array
                    byte[] imageBytes = new byte[fuAttachFile.PostedFile.InputStream.Length + 1];
                    fuAttachFile.PostedFile.InputStream.Read(imageBytes, 0, imageBytes.Length);

                    cmd.Parameters.AddWithValue("@tkt_id", SqlDbType.Int).Value = TicketID;
                    cmd.Parameters.AddWithValue("@usr_req_chg_id", SqlDbType.Int).Value = ddlUserRequestingChange.SelectedItem.Value;
                    cmd.Parameters.AddWithValue("@req_typ_id", SqlDbType.Int).Value = ddlRequestType.SelectedItem.Value;
                    cmd.Parameters.AddWithValue("@com_id", SqlDbType.Int).Value = ddlCompany.SelectedItem.Value;
                    cmd.Parameters.AddWithValue("@sts_id", SqlDbType.Int).Value = ddlStatusType.SelectedItem.Value;
                    cmd.Parameters.AddWithValue("@ownr_id", SqlDbType.Int).Value = ddlTicketOwner.SelectedItem.Value;
                    cmd.Parameters.AddWithValue("@tkt_desc", SqlDbType.VarChar).Value = txtTicketDesc.Text;
                    cmd.Parameters.AddWithValue("@tkt_resolution", SqlDbType.VarChar).Value = txtTicketResolution.Text;
                    cmd.Parameters.AddWithValue("@tkt_file", SqlDbType.Image).Value = imageBytes;
                    cmd.Parameters.AddWithValue("@tkt_filename", SqlDbType.VarChar).Value = filename;
                    cmd.Parameters.AddWithValue("@tkt_mime", SqlDbType.VarChar).Value = MIMEType;
                    cmd.Parameters.AddWithValue("@tkt_size", SqlDbType.VarChar).Value = fileSize;

                    if (string.IsNullOrEmpty(txtCompletionDate.Text))
                    {
                        cmd.Parameters.AddWithValue("@tkt_cmpl_dt", SqlDbType.DateTime).Value = DBNull.Value;
                    }
                    else
                    {
                        cmd.Parameters.AddWithValue("@tkt_cmpl_dt", SqlDbType.DateTime).Value = txtCompletionDate.Text;
                    }

                    try
                    {
                        conn.Open();
                        cmd.ExecuteNonQuery();
                    }

                    catch (Exception ex)
                    {
                        lblInsertError.Visible = true;
                        lblInsertError.Text = ("Error on insert: " + ex.Message.ToString());
                    }

                    finally
                    {
                        Response.Redirect("index.aspx");
                        conn.Close();
                    }
                }

                else
                {
                    lblFileSize.Visible = true;
                    lblFileSize.Text = "File size must be 1MB or smaller.";
                }
            }
            else  // no file has been uploaded, we only need to update txtPhysicalDateCompleted
            {
                SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["CMDB"].ConnectionString);

                SqlCommand cmd = new SqlCommand();
                cmd.CommandText = "ModifyTicket";
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Connection = conn;

                byte[] imageBytes = new byte[1];

                cmd.Parameters.AddWithValue("@tkt_id", SqlDbType.Int).Value = TicketID;
                cmd.Parameters.AddWithValue("@usr_req_chg_id", SqlDbType.Int).Value = ddlUserRequestingChange.SelectedItem.Value;
                cmd.Parameters.AddWithValue("@req_typ_id", SqlDbType.Int).Value = ddlRequestType.SelectedItem.Value;
                cmd.Parameters.AddWithValue("@com_id", SqlDbType.Int).Value = ddlCompany.SelectedItem.Value;
                cmd.Parameters.AddWithValue("@sts_id", SqlDbType.Int).Value = ddlStatusType.SelectedItem.Value;
                cmd.Parameters.AddWithValue("@ownr_id", SqlDbType.Int).Value = ddlTicketOwner.SelectedItem.Value;
                cmd.Parameters.AddWithValue("@tkt_desc", SqlDbType.VarChar).Value = txtTicketDesc.Text;
                cmd.Parameters.AddWithValue("@tkt_resolution", SqlDbType.VarChar).Value = txtTicketResolution.Text;
                cmd.Parameters.AddWithValue("@tkt_file", SqlDbType.Image).Value = imageBytes;
                cmd.Parameters.AddWithValue("@tkt_filename", SqlDbType.VarChar).Value = "";
                cmd.Parameters.AddWithValue("@tkt_mime", SqlDbType.VarChar).Value = "application/octet-stream";
                cmd.Parameters.AddWithValue("@tkt_size", SqlDbType.VarChar).Value = 0;

                if (string.IsNullOrEmpty(txtCompletionDate.Text))
                {
                    cmd.Parameters.AddWithValue("@tkt_cmpl_dt", SqlDbType.DateTime).Value = DBNull.Value;
                }
                else
                {
                    cmd.Parameters.AddWithValue("@tkt_cmpl_dt", SqlDbType.DateTime).Value = txtCompletionDate.Text;
                }

                try
                {
                    conn.Open();
                    cmd.ExecuteNonQuery();
                }

                catch (Exception ex)
                {
                    lblInsertError.Visible = true;
                    lblInsertError.Text = ("Error on insert: " + ex.Message.ToString());
                }

                finally
                {
                    Response.Redirect("index.aspx");
                    conn.Close();
                }
            }
        }
    }