Gridview coder

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text.RegularExpressions;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace aspnet_administartion
{
    public partial class _Default : Page
    {

        DataClasses1DataContext db = new DataClasses1DataContext();
        bool flagEmptyRow = false;//vlajka pro zobrazeni gridview - když je prázdne
        protected void Page_Load(object sender, EventArgs e)
        {
            //vyresetovaní flajky
            flagEmptyRow = false;
        }
        protected void PageRender(object sender, EventArgs e)
        {
            if (flagEmptyRow)
            {
                // skrytí prazndeho řádku
                GridView1.Rows[0].Visible = false;
            }
        }
        /// <summary>
        ///    nastaveni filtru
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void LinqSource_Selecting(object sender, LinqDataSourceSelectEventArgs e)
        {
            //switch pro nastaveni filtru
            switch (SetFilter.Value)
            {
                case "name":
                    e.Result = db.Restaurants.Where(p => p.Name.ToLower().Contains(searchString.Text.ToLower()));
                    break;
                case "phone":
                    e.Result = db.Restaurants.Where(p => p.Phone.ToLower().Contains(searchString.Text.ToLower()));
                    break;
                case "mail":
                    e.Result = db.Restaurants.Where(p => p.Email.ToLower().Contains(searchString.Text.ToLower()));
                    break;
                default:
                    if (db.Restaurants.Count() == 0)//pokud je gridview prazdny a neni nastavena filtrace vytvori falseny řádek
                    {
                        e.Result = new Restaurant();
                        flagEmptyRow = true;//nastaveni vlajky pro schovani falesneho radku
                    }
                    else
                        e.Result = db.Restaurants;
                    break;
            }

        }
        protected void LinqSource_Selected(object sender, LinqDataSourceStatusEventArgs e)
        {

        }
        /// <summary>
        ///     zruseni pridani nove restaurace
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void CancelNew_Click(object sender, EventArgs e)
        {
            GridViewRow row = (GridViewRow)((sender as Button).NamingContainer);
            //vyčištění polí
            ((TxtBox)row.FindControl("NewName")).Value = "";
            ((TxtBox)row.FindControl("NewPhone")).Value = "";
            ((TxtBox)row.FindControl("NewEmail")).Value = "";
        }
        /// <summary>
        ///    ulozeni nove restaurace
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void SaveNew_Click(object sender, EventArgs e)
        {
            // This is the crux -
            GridViewRow row = (GridViewRow)((sender as Button).NamingContainer);
            Restaurant r = new Restaurant();
            //nalezeni ovladacich prvků
            TxtBox txtName = (TxtBox)row.FindControl("NewName");
            TxtBox txtPhone = (TxtBox)row.FindControl("NewPhone");
            TxtBox txtMail = (TxtBox)row.FindControl("NewEmail");

            //serverova validace
            if (db.Restaurants.Any(p => p.Name == txtName.Value))
            {
                errorBox.Controls.Add(new LiteralControl("Jméno musí být 3-50 znaků dlouhé"));
                return;
            }
            //serverova validace
            if (Regex.IsMatch(txtName.Value, @".{3,50}"))
            {
                errorBox.Controls.Add(new LiteralControl("header musí být 3-30 znaků dlouhý"));
                return;
            }
            r.Name = txtName.Value;
            //serverova validace
            if (Regex.IsMatch(txtPhone.Value, @"^[0-9]{3} [0-9]{3} [0-9]{3}$"))
            {
                errorBox.Controls.Add(new LiteralControl("Zadejte telefon ve formátu 123 456 789"));
                return;
            }
            r.Phone = txtPhone.Value;
            //serverova validace
            if (Regex.IsMatch(txtMail.Value, @"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,3})+)$"))
            {
                errorBox.Controls.Add(new LiteralControl("Zadejte validní email"));
                return;
            }

            r.Email = txtMail.Value;
            db.Restaurants.InsertOnSubmit(r);
            db.SubmitChanges();

            GridView1.DataBind();
        }
        /// <summary>
        ///   zacatek editace
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void Edit_Click(object sender, EventArgs e)
        {
            //spusteni editačního modu
            GridViewRow row = (GridViewRow)((sender as Button).NamingContainer);
            GridView1.EditIndex = row.RowIndex;

        }
        /// <summary>
        ///  konec editace
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void CancelEdit_Click(object sender, EventArgs e)
        {
            // neni receno jestli se maji vynulovat data - tak je nechávám být a vypinam validacni mod
            GridView1.EditIndex = -1;
        }
        /// <summary>
        ///    ukladani članků
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void SaveArticle_Click(object sender, EventArgs e)
        {
            GridViewRow row = (GridViewRow)((sender as Button).NamingContainer);


            Label lblname = (Label)row.FindControl("lblName");
            Button btnNew = (Button)row.FindControl("SetNewArticle");

            ArticlePanel arrPanel = (ArticlePanel)row.FindControl("articlePanel");
            arrPanel.RestauraceId = lblname.Text; //ziskani restaurant ID
            arrPanel.NewArticle = !btnNew.Visible;  // bool pro zjisteni - jestli se jedna o novy clanek nebo o upravu
            if (arrPanel.SaveEvent())//pokud probehlo ulozeni - vracim gridview do pivodni podoby
            {

                SetVisibile(row, "EditingPanel", false);
                SetVisibile(row, "ClosePanel", false);
                SetVisibile(row, "Edit", true);

                SetVisibile(row, "SetNewArticle", false);
                SetVisibile(row, "ShowFrom", true);
            }
        }
        /// <summary>
        ///    zobrazeni formulare članku
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void ShowFrom_Click(object sender, EventArgs e)
        {
            GridViewRow row = (GridViewRow)((sender as Button).NamingContainer);

            Label lblname = (Label)row.FindControl("lblName");
            ArticlePanel arrPanel = (ArticlePanel)row.FindControl("articlePanel");
            arrPanel.RestauraceId = lblname.Text;
            arrPanel.FillDropDownList();

            SetVisibile(row, "EditingPanel", true);
            SetVisibile(row, "ClosePanel", true);
            SetVisibile(row, "Edit", false);

            SetVisibile(row, "SetNewArticle", true);
            SetVisibile(row, "ShowFrom", false);

        }
        /// <summary>
        ///    ukocení spravy članku
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void ClosePanel_Click(object sender, EventArgs e)
        {
            GridViewRow row = (GridViewRow)((sender as Button).NamingContainer);

            ArticlePanel arrPanel = (ArticlePanel)row.FindControl("articlePanel");
            arrPanel.NewArticle = false;
            arrPanel.ClearTxt();
            //zaviram celou editaci - nevim zda-li jsem spravne pochopil
            SetVisibile(row, "EditingPanel", false);
            SetVisibile(row, "ClosePanel", false);
            SetVisibile(row, "Edit", true);

            SetVisibile(row, "SetNewArticle", false);
            SetVisibile(row, "ShowFrom", true);
        }
        /// <summary>
        ///     nastaveni modu novy članek
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void SetNewArticle_Click(object sender, EventArgs e)
        {
            GridViewRow row = (GridViewRow)((sender as Button).NamingContainer);

            ArticlePanel arrPanel = (ArticlePanel)row.FindControl("articlePanel");
            arrPanel.NewArticle = true;// tento parametr nastavi pohled na pridavani novych članků

            SetVisibile(row, "SetNewArticle", false);
        }
        /// <summary>
        ///    funkce pro shovavani a zobrazovani ovladacivh prvku v zaznamu (Row)
        /// </summary>
        /// <param name="row"> radek gridu</param>
        /// <param name="nameControl">nazev prvku</param>
        /// <param name="visible">jaky stav ma byt nastaven</param>
        protected void SetVisibile(GridViewRow row, string nameControl, bool visible)
        {
            Control control = row.FindControl(nameControl);
            control.Visible = visible;
        }
        /// <summary>
        ///    udalost nastaveni filtru
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void Filter_Click(object sender, EventArgs e)
        {
            SetFilter.Value = Type.SelectedValue;
            GridView1.DataBind();

        }
        /// <summary>
        ///   udalost zrušení filtru
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void ShowAll_Click(object sender, EventArgs e)
        {
            SetFilter.Value = "";
            GridView1.DataBind();
        }


    }
}