elma/ELMA/Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.Entity;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using AppData;

namespace ELMA
{
    public partial class MainForm : Form
    {
        ElmahModel model = new ElmahModel();



        public MainForm()
        {
            InitializeComponent();
            myInit();
        }

        private void myInit()
        {
            // carico DB con filtri
            //var setApp = dbFilt.Where(x => x.Cat == "Application");
            var setApp = model.ELMAH_Error
                         .Select(e => new { e.Application })
                         .Distinct()
                         .ToList();
            foreach (var item in setApp)
            {
                listApp.Items.Add(item.Application);
            }
            listApp.SelectedIndex = 0;
            var setHost = model.ELMAH_Error
                         .Select(e => new { e.Host })
                         .Distinct()
                         .ToList();
            foreach (var item in setHost)
            {
                listHost.Items.Add(item.Host);
            }
            listHost.SelectedIndex = 0;
            var setStatus = model.ELMAH_Error
                         .Select(e => new { e.StatusCode })
                         .Distinct()
                         .ToList();
            foreach (var item in setStatus)
            {
                listStatus.Items.Add(item.StatusCode);
            }
            listStatus.SelectedIndex = 0;
            var setType = model.ELMAH_Error
                         .Select(e => new { e.Type })
                         .Distinct()
                         .ToList();
            foreach (var item in setType)
            {
                listType.Items.Add(item.Type);
            }
            listType.SelectedIndex = 0;
            var setUser = model.ELMAH_Error
                         .Select(e => new { e.User })
                         .Distinct()
                         .ToList();
            //var setUser = dbFilt.Where(x => x.Cat == "User").ToList();
            foreach (var item in setUser)
            {
                listUsers.Items.Add(item.User);
            }
            listUsers.SelectedIndex = 0;
        }

        protected string selApp { get { return listApp.SelectedItem.ToString(); } }
        protected string selStatus { get { return listStatus.SelectedItem.ToString(); } }
        protected string selHost { get { return listHost.SelectedItem.ToString(); } }
        protected string selType { get { return listType.SelectedItem.ToString(); } }
        protected string selUser { get { return listUsers.SelectedItem.ToString(); } }


        private void btnLoad_Click(object sender, EventArgs e)
        {
            updateSelection();
            //this.bsErrors.DataSource = model.ELMAH_Error.Local.ToBindingList();
        }

        private void updateSelection()
        {
            List<ELMAH_Error> subset = getFiltData();
            this.bsErrors.DataSource = subset;
        }

        private List<ELMAH_Error> getFiltData()
        {
            var dbSet = model.ELMAH_Error;
            int statusCode = 0;
            int.TryParse(selStatus, out statusCode);
            string selApp = listApp.SelectedItem.ToString();
            // fix DGV
            var subset = dbSet.Where(x =>
                  x.StatusCode == statusCode
                 && x.Application == selApp
                 && x.Host == selHost
                 && x.Type == selType
                 && x.User == selUser
               ).ToList();
            return subset;
        }

        private void listApp_SelectedIndexChanged(object sender, EventArgs e)
        {
            //updateSelection();
        }

        private void listHost_SelectedIndexChanged(object sender, EventArgs e)
        {
            //updateSelection();
        }

        private void listStatus_SelectedIndexChanged(object sender, EventArgs e)
        {
            //updateSelection();
        }

        private void listType_SelectedIndexChanged(object sender, EventArgs e)
        {
            //updateSelection();
        }

        private void listUsers_SelectedIndexChanged(object sender, EventArgs e)
        {
            //updateSelection();
        }

        private void btnDelete_Click(object sender, EventArgs e)
        {
            // elimino 1:1 da selezione
            foreach (var item in getFiltData())
            {
                model.ELMAH_Error.Remove(item);
            }

            // salvo
            model.SaveChangesAsync();

            // aggiorno
            updateSelection();
        }
    }
}