protected void btncancel_Click(object sender, EventArgs e)
 {
     GridviewUpload.DataSource = null;
     GridviewUpload.DataBind();
     GridviewUpload.Visible   = false;
     GridviewProducts.Visible = true;
     btnupload.Text           = "Upload";
     lblupload.ForeColor      = System.Drawing.Color.Blue;
     lblupload.Text           = "Upload Multiple Product";
     btncancel.Visible        = false;
     Handler.Load("Select ProductName, Quantity, CostPrice, SellingPrice from tblProducts", GridviewProducts);
 }
        protected void btnupload_Click(object sender, EventArgs e)
        {
            if (btnupload.Text == "Upload")
            {
                GridviewProducts.Visible = false;

                if (FileUpload1.HasFile)
                {
                    string fileextention = System.IO.Path.GetExtension(FileUpload1.FileName);
                    //FileInfo fileInfo = new FileInfo(FileUpload1.PostedFile.FileName);
                    //if (fileInfo.Name.Contains(".csv"))

                    if (fileextention.ToLower() == ".csv")
                    {
                        string csvPath = Server.MapPath("~/Files/") + Path.GetFileName(FileUpload1.PostedFile.FileName);
                        FileUpload1.SaveAs(csvPath);

                        //Create a DataTable.
                        DataTable dt = new DataTable();
                        dt.Columns.AddRange(new DataColumn[6] {
                            new DataColumn("Id", typeof(string)),
                            new DataColumn("Product Name", typeof(string)),
                            new DataColumn("Quantity", typeof(string)),
                            new DataColumn("Cost Price", typeof(string)),
                            new DataColumn("Selling Price", typeof(string)),
                            new DataColumn("Category", typeof(string))
                        });

                        //Read the contents of CSV file.
                        string csvData = File.ReadAllText(csvPath);

                        foreach (string row in csvData.Split('\n'))
                        {
                            if (!string.IsNullOrEmpty(row))
                            {
                                dt.Rows.Add();
                                int i = 1;

                                //Execute a loop over the columns.
                                foreach (string cell in row.Split(','))
                                {
                                    for (int j = 1; j <= dt.Rows.Count; j++)
                                    {
                                        dt.Rows[dt.Rows.Count - 1][0] = j;
                                    }
                                    //string id = Handler.GenerateId();
                                    //
                                    dt.Rows[dt.Rows.Count - 1][i] = cell;
                                    i++;
                                }
                            }
                        }


                        //Bind the DataTable.
                        Session["Dt"]             = dt;
                        GridviewUpload.Visible    = true;
                        GridviewUpload.DataSource = dt;
                        GridviewUpload.DataBind();
                        if (GridviewUpload.Rows.Count > 0)
                        {
                            btnupload.Text      = "Save this upload";
                            btncancel.Visible   = true;
                            lblupload.ForeColor = System.Drawing.Color.Green;
                            lblupload.Text      = "Upload was successfull <br/><b>Please Preview before saving</b";
                        }
                    }
                    else
                    {
                        lblupload.ForeColor = System.Drawing.Color.Red;
                        lblupload.Text      = "Only .csv files are allowed";
                    }
                }
                else
                {
                    lblupload.ForeColor = System.Drawing.Color.Red;
                    lblupload.Text      = "Upload a file(.csv)";
                }
            }
            else if (btnupload.Text == "Save this upload")
            {
                string CS = ConfigurationManager.ConnectionStrings["Connect"].ConnectionString;

                //using (SqlConnection con = new SqlConnection(CS))
                //{
                //    SqlCommand cmd = new SqlCommand("Select * From tblCategory", con);
                //    con.Open();
                //    SqlDataReader dr = cmd.ExecuteReader();
                //    for (int i = 0; i <= GridviewProducts.Rows.Count - 1; i++)
                //    {
                //        if (GridviewProducts.Rows[i].Cells[6].Text == (string)dr["CategoryName"])
                //        {
                //            Lbluser.Text = "THERE is an error";
                //        }
                //        //GridviewProducts.Rows[i].Cells[6].Text
                //    }
                //}



                var table = "tblProducts";
                using (SqlConnection con = new SqlConnection(CS))
                {
                    var bulkCopy = new SqlBulkCopy(con);
                    bulkCopy.DestinationTableName = table;
                    DataTable dt = new DataTable();
                    dt = (DataTable)Session["Dt"];
                    con.Open();
                    bulkCopy.WriteToServer(dt);
                    lblupload.ForeColor = System.Drawing.Color.Green;
                    lblupload.Text      = "File was saved successfully";
                    btncancel.Enabled   = false;
                    btnupload.Text      = "Upload";
                }
            }
        }