BookStore_Framework472/BookStore/MainWindow.xaml.cs

using System.Linq;
using System.Windows;
using System.Windows.Controls;

namespace BookStore
{
    public partial class MainWindow : Window
    {
        dbBookStoreEntities db = new dbBookStoreEntities();

        public MainWindow() {InitializeComponent(); Load();}

        public void Load() { BooksGrid.ItemsSource = db.Books.ToList(); }

        private void BtnInsert_Click(object sender, RoutedEventArgs e) {BIC();}
        public void BIC()
        {
            if (!decimal.TryParse(TbPrice.Text, out decimal price)) {return;}
            Book book = new Book()
            {
                Name = TbName.Text,
                Price = price,
                Author = TbAuthor.Text,
                Category = TbCategory.Text
            };
            db.Books.Add(book); db.SaveChanges(); Load();
        }

        private void BtnUpdate_Click(object sender, RoutedEventArgs e) {BUC();}
        public void BUC()
        {
            if (BooksGrid.SelectedItem is Book selectedBook)
            {
                if (!decimal.TryParse(TbPrice.Text, out decimal price)) {return;}
                selectedBook.Name = TbName.Text;
                selectedBook.Price = price;
                selectedBook.Author = TbAuthor.Text;
                selectedBook.Category = TbCategory.Text;
                db.SaveChanges(); Load();
            }
        }

        private void BtnDelete_Click(object sender, RoutedEventArgs e) {BDC();}
        public void BDC()
        {
            if (BooksGrid.SelectedItem is Book selectedBook)
            { db.Books.Remove(selectedBook); db.SaveChanges(); TbClear(); Load(); }
        }
        public void TbClear() 
        { TbName.Text = ""; TbPrice.Text = ""; TbAuthor.Text = ""; TbCategory.Text = ""; }

        private void BooksGrid_SelectionChanged(object sender, SelectionChangedEventArgs e) {BGSC();}
        public void BGSC()
        {
            if (BooksGrid.SelectedItem is Book selectedBook)
            {
                TbName.Text = selectedBook.Name;
                TbPrice.Text = selectedBook.Price.ToString();
                TbAuthor.Text = selectedBook.Author;
                TbCategory.Text = selectedBook.Category;
            }
        }
    }
}