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博客园 - FredGrit

WPF customize via three combied custom controls WPF DataGrid DataGridTemplateColumn DataTemplate ContentPresenter ContentTemplate WPF Customcontrol NumUpDownScroller WPF CustomControl override Template in Generic.xaml and invoke different style WPF HierarchicalDataTemplate customize via ToggleButton WPF DataGrid DataGridTemplateColumn DataTemplate call predefined DataTemplate via ContentPresenter and ContentTemplate WPF ListBox load data via contentcontrol an ItemTemplate WPF DataGrid load data from Asp.Net Core WebAPI WPF TreeView HierarchicalDataTemplate with grouped Data WPF display grouped data with GroupBox and ItemsControl WPF two listbox scroll syncchronously via behavior WPF invoke data from WebAPI,DataGridTemplate call pre defined DataTemplate via ContentPresenter WPF ListBox load data from WCF WPF datagrid load data from WCF via json, export selected items to json file WPF ItemsControl load data from WCF,DataTemplate, ContentControl WPF customize rotated wheel relentlessly via custom control WPF embed DataTemplate in HierchicalDataTemplate of TreeView WPF ContentControl, ItemsControl, ItemsPanelTemplate,VirtualizingStackPanel,convert xml string to List<T> WPF parse web.config recursively, TreeView and HierarchicalDataTemplate WPF Custom control in cs and Generic.xaml WPF ContextMenu independent visual tree resolved via Freezable implemented class WPF custom control GetTemplateChild vs FindName,NameScope separation between Logical Tree and Visual Tree, WPF ListBox ListView Datatemplate, parse xml to List via XmlSerializer and StringReader WPF TreeView HierarchicalDataTemplate, parse xml via traverse in XmlElement WPF parse xml via [XmRoot] and [XmlElement] attributes together, contentcontrol's template is ControlTemplate from Resources WPF ContentControl invoke Template from resource, reuse datatemplate WPF deserialize xml string as List via [XmlRoot] and [XmlElement] attribute WPF ContentControl Template WPF DatagridTemplate Binding DataTemplate WPF TreeView explicitly given key name to HierarchicalDataTemplate
WPF ItemsControl IsItemsHost=True
FredGrit · 2026-04-07 · via 博客园 - FredGrit
 <ItemsControl ItemsSource="{Binding BooksCollection}">
     <ItemsControl.Template>
         <ControlTemplate TargetType="ItemsControl">
             <DockPanel LastChildFill="True">
                 <TextBlock Text="IsItemsHost=True" FontSize="50" 
                            DockPanel.Dock="Top"/>
                 <ScrollViewer CanContentScroll="True">
                     <VirtualizingStackPanel IsItemsHost="True"
                              VirtualizingPanel.IsVirtualizing="True"
                              VirtualizingPanel.VirtualizationMode="Recycling"
                              ScrollViewer.CanContentScroll="True"
                              ScrollViewer.IsDeferredScrollingEnabled="True"                                                        
                              VirtualizingPanel.CacheLength="2,2"
                              VirtualizingPanel.CacheLengthUnit="Item">
                     </VirtualizingStackPanel>
                 </ScrollViewer>
             </DockPanel>
         </ControlTemplate>
     </ItemsControl.Template>
     <ItemsControl.ItemTemplate>
         <DataTemplate>
             <Grid Margin="5" Width="{x:Static SystemParameters.FullPrimaryScreenWidth}" 
                   Height="{x:Static SystemParameters.FullPrimaryScreenHeight}">
                 <Grid.RowDefinitions>
                     <RowDefinition/>
                     <RowDefinition/>
                 </Grid.RowDefinitions>
                 <Grid.ColumnDefinitions>
                     <ColumnDefinition/>
                     <ColumnDefinition/>
                 </Grid.ColumnDefinitions>
                 <Grid.Resources>
                     <Style TargetType="TextBlock">
                         <Setter Property="FontSize" Value="30"/>
                         <Style.Triggers>
                             <Trigger Property="IsMouseOver" Value="True">
                                 <Setter Property="FontSize" Value="50"/>
                                 <Setter Property="Foreground" Value="Red"/>
                             </Trigger>
                         </Style.Triggers>
                     </Style>
                 </Grid.Resources>
                 <Image Source="{Binding ImgUrl,Converter={StaticResource ImgConverter}}"
                            Stretch="Uniform"
                            Grid.Row="0"
                            Grid.RowSpan="2"
                            Grid.Column="0"
                            Grid.ColumnSpan="2"/>
                 <TextBlock Text="{Binding Id}" Grid.Row="0" Grid.Column="0"/>
                 <TextBlock Text="{Binding Name}" Grid.Row="0" Grid.Column="1"/>
                 <TextBlock Text="{Binding ISBN}" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2"/>
             </Grid>
         </DataTemplate>
     </ItemsControl.ItemTemplate>
 </ItemsControl>

image

<Window x:Class="WpfApp12.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp12"
        mc:Ignorable="d"
        WindowState="Maximized"
        Title="{Binding MainTitle}">
    <Window.DataContext>
        <local:MainVM/>
    </Window.DataContext>
    <Window.Resources>
        <local:ImgConverter x:Key="ImgConverter"/>
    </Window.Resources>
    <Grid>
        <ItemsControl ItemsSource="{Binding BooksCollection}">
            <ItemsControl.Template>
                <ControlTemplate TargetType="ItemsControl">
                    <DockPanel LastChildFill="True">
                        <TextBlock Text="IsItemsHost=True" FontSize="50" 
                                   DockPanel.Dock="Top"/>
                        <ScrollViewer CanContentScroll="True">
                            <VirtualizingStackPanel IsItemsHost="True"
                                     VirtualizingPanel.IsVirtualizing="True"
                                     VirtualizingPanel.VirtualizationMode="Recycling"
                                     ScrollViewer.CanContentScroll="True"
                                     ScrollViewer.IsDeferredScrollingEnabled="True"                                                        
                                     VirtualizingPanel.CacheLength="2,2"
                                     VirtualizingPanel.CacheLengthUnit="Item">
                            </VirtualizingStackPanel>
                        </ScrollViewer>
                    </DockPanel>
                </ControlTemplate>
            </ItemsControl.Template>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Grid Margin="5" Width="{x:Static SystemParameters.FullPrimaryScreenWidth}" 
                          Height="{x:Static SystemParameters.FullPrimaryScreenHeight}">
                        <Grid.RowDefinitions>
                            <RowDefinition/>
                            <RowDefinition/>
                        </Grid.RowDefinitions>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition/>
                            <ColumnDefinition/>
                        </Grid.ColumnDefinitions>
                        <Grid.Resources>
                            <Style TargetType="TextBlock">
                                <Setter Property="FontSize" Value="30"/>
                                <Style.Triggers>
                                    <Trigger Property="IsMouseOver" Value="True">
                                        <Setter Property="FontSize" Value="50"/>
                                        <Setter Property="Foreground" Value="Red"/>
                                    </Trigger>
                                </Style.Triggers>
                            </Style>
                        </Grid.Resources>
                        <Image Source="{Binding ImgUrl,Converter={StaticResource ImgConverter}}"
                                   Stretch="Uniform"
                                   Grid.Row="0"
                                   Grid.RowSpan="2"
                                   Grid.Column="0"
                                   Grid.ColumnSpan="2"/>
                        <TextBlock Text="{Binding Id}" Grid.Row="0" Grid.Column="0"/>
                        <TextBlock Text="{Binding Name}" Grid.Row="0" Grid.Column="1"/>
                        <TextBlock Text="{Binding ISBN}" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2"/>
                    </Grid>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </Grid>
</Window>


using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Globalization;
using System.IO;
using System.Runtime.CompilerServices;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp12
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
    }

    public class MainVM : INotifyPropertyChanged
    {
        private DateTime startTime;
        public MainVM()
        {
            Task.Run(async () =>
            {
                await InitBooksCollection(52600000);
            });
        }
        public async Task InitBooksCollection(int cnt = 100000)
        {
            BooksCollection = new ObservableCollection<Book>();
            List<Book> booksList = new List<Book>();
            var imgDir = @"../../../Images";
            if (!Directory.Exists(imgDir))
            {
                return;
            }
            var imgs = Directory.GetFiles(imgDir);
            if (imgs == null || !imgs.Any())
            {
                return;
            }
            int imgsCount = imgs.Count();

            startTime = DateTime.Now;
            for (int i = 1; i < cnt + 1; i++)
            {
                booksList.Add(new Book()
                {
                    Id = i,
                    Name = $"Name_{i}",
                    ISBN = $"ISBN_{i}_{Guid.NewGuid():N}",
                    ImgUrl = $"{imgs[i % imgsCount]}"
                });

                if (i < 1000 && i % 200 == 0)
                {
                    await PopulateBooksCollectionAsync(booksList);
                    await Task.Delay(1);
                }

                else if (i % 1000000 == 0)
                {
                    await PopulateBooksCollectionAsync(booksList);
                    await Task.Delay(1);
                }
            }

            if (booksList.Any())
            {
                await PopulateBooksCollectionAsync(booksList);
            }
        }

        private async Task PopulateBooksCollectionAsync(List<Book> booksList)
        {
            var tempList = booksList.ToList();
            await Application.Current.Dispatcher.InvokeAsync(() =>
            {
                foreach (var bk in tempList)
                {
                    BooksCollection.Add(bk);
                }
                MainTitle = $"{DateTime.Now},loaded {BooksCollection.Count} items,{GetMem()},{GetTimeCost()}";
                booksList.Clear();
            }, System.Windows.Threading.DispatcherPriority.Background);
        }

        public string GetTimeCost()
        {
            var dtSpan = DateTime.Now.Subtract(startTime);
            return $"Time cost {dtSpan.TotalSeconds:0.00} seconds";
        }

        private string GetMem()
        {
            return $"{System.Diagnostics.Process.GetCurrentProcess().PrivateMemorySize64 / 1024 / 1024:N2} M";
        }

        private string mainTitle = "";
        public string MainTitle
        {
            get
            {
                return mainTitle;
            }
            set
            {
                if (value != mainTitle)
                {
                    mainTitle = value;
                    OnPropertyChanged();
                }
            }
        }

        private ObservableCollection<Book> booksCollection;
        public ObservableCollection<Book> BooksCollection
        {
            get
            {
                return booksCollection;
            }
            set
            {
                if (value != booksCollection)
                {
                    booksCollection = value;
                    OnPropertyChanged();
                }
            }
        }

        public event PropertyChangedEventHandler? PropertyChanged;
        private void OnPropertyChanged([CallerMemberName] string propertyName = "")
        {
            var handler = PropertyChanged;
            handler?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }

    public class ImgConverter : IValueConverter
    {
        private Dictionary<string, ImageSource> imgCache = new Dictionary<string, ImageSource>();
        private readonly object objLock = new object();
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            var imgUrl = value?.ToString();
            if (string.IsNullOrWhiteSpace(imgUrl) || !File.Exists(imgUrl))
            {
                return null;
            }

            lock (objLock)
            {
                if (imgCache.ContainsKey(imgUrl))
                {
                    return imgCache[imgUrl];
                }

                BitmapImage bmi = new BitmapImage();
                bmi.BeginInit();
                bmi.UriSource = new Uri(imgUrl, UriKind.RelativeOrAbsolute);
                //bmi.DecodePixelWidth = 1200;
                //bmi.DecodePixelHeight = 700;
                bmi.CacheOption = BitmapCacheOption.OnLoad;
                bmi.EndInit();
                if (bmi.CanFreeze)
                {
                    bmi.Freeze();
                }
                imgCache[imgUrl] = bmi;
                return bmi;
            }
            return null;
        }


        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            return DependencyProperty.UnsetValue;
        }
    }


    public class DelCommand : ICommand
    {
        private Action<object?>? execute;
        private Predicate<object?>? canExecute;
        public DelCommand(Action<object?>? executeValue, Predicate<object?>? canExecuteValue = null)
        {
            execute = executeValue;
            canExecute = canExecuteValue;
        }

        public event EventHandler? CanExecuteChanged
        {
            add
            {
                CommandManager.RequerySuggested += value;
            }
            remove
            {
                CommandManager.RequerySuggested -= value;
            }
        }

        public bool CanExecute(object? parameter)
        {
            return canExecute == null ? true : canExecute(parameter);
        }

        public void Execute(object? parameter)
        {
            execute?.Invoke(parameter);
        }
    }


    public class Book
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string ISBN { get; set; }
        public string ImgUrl { get; set; }
    }

}

image

 <ItemsControl ItemsSource="{Binding BooksCollection}">
     <ItemsControl.Template>
         <ControlTemplate TargetType="ItemsControl">
             <ScrollViewer CanContentScroll="True">
                 <VirtualizingStackPanel IsItemsHost="True"
                              VirtualizingPanel.IsVirtualizing="True"
                              VirtualizingPanel.VirtualizationMode="Recycling"
                              ScrollViewer.CanContentScroll="True"
                              ScrollViewer.IsDeferredScrollingEnabled="True"                                                        
                              VirtualizingPanel.CacheLength="2,2"
                              VirtualizingPanel.CacheLengthUnit="Item"/> 
             </ScrollViewer>
         </ControlTemplate>
     </ItemsControl.Template>
     <ItemsControl.ItemTemplate>
         <DataTemplate>
             <Grid Margin="5" Width="{x:Static SystemParameters.FullPrimaryScreenWidth}" 
                   Height="{x:Static SystemParameters.FullPrimaryScreenHeight}">
                 <Grid.RowDefinitions>
                     <RowDefinition/>
                     <RowDefinition/>
                 </Grid.RowDefinitions>
                 <Grid.ColumnDefinitions>
                     <ColumnDefinition/>
                     <ColumnDefinition/>
                 </Grid.ColumnDefinitions>
                 <Grid.Resources>
                     <Style TargetType="TextBlock">
                         <Setter Property="FontSize" Value="30"/>
                         <Style.Triggers>
                             <Trigger Property="IsMouseOver" Value="True">
                                 <Setter Property="FontSize" Value="50"/>
                                 <Setter Property="Foreground" Value="Red"/>
                             </Trigger>
                         </Style.Triggers>
                     </Style>
                 </Grid.Resources>
                 <Image Source="{Binding ImgUrl,Converter={StaticResource ImgConverter}}"
                            Stretch="Uniform"
                            Grid.Row="0"
                            Grid.RowSpan="2"
                            Grid.Column="0"
                            Grid.ColumnSpan="2"/>
                 <TextBlock Text="{Binding Id}" Grid.Row="0" Grid.Column="0"/>
                 <TextBlock Text="{Binding Name}" Grid.Row="0" Grid.Column="1"/>
                 <TextBlock Text="{Binding ISBN}" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2"/>
             </Grid>
         </DataTemplate>
     </ItemsControl.ItemTemplate>
 </ItemsControl>
<Window x:Class="WpfApp12.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp12"
        mc:Ignorable="d"
        WindowState="Maximized"
        Title="{Binding MainTitle}">
    <Window.DataContext>
        <local:MainVM/>
    </Window.DataContext>
    <Window.Resources>
        <local:ImgConverter x:Key="ImgConverter"/>
    </Window.Resources>
    <Grid>
        <ItemsControl ItemsSource="{Binding BooksCollection}">
            <ItemsControl.Template>
                <ControlTemplate TargetType="ItemsControl">
                    <ScrollViewer CanContentScroll="True">
                        <VirtualizingStackPanel IsItemsHost="True"
                                     VirtualizingPanel.IsVirtualizing="True"
                                     VirtualizingPanel.VirtualizationMode="Recycling"
                                     ScrollViewer.CanContentScroll="True"
                                     ScrollViewer.IsDeferredScrollingEnabled="True"                                                        
                                     VirtualizingPanel.CacheLength="2,2"
                                     VirtualizingPanel.CacheLengthUnit="Item"/> 
                    </ScrollViewer>
                </ControlTemplate>
            </ItemsControl.Template>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Grid Margin="5" Width="{x:Static SystemParameters.FullPrimaryScreenWidth}" 
                          Height="{x:Static SystemParameters.FullPrimaryScreenHeight}">
                        <Grid.RowDefinitions>
                            <RowDefinition/>
                            <RowDefinition/>
                        </Grid.RowDefinitions>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition/>
                            <ColumnDefinition/>
                        </Grid.ColumnDefinitions>
                        <Grid.Resources>
                            <Style TargetType="TextBlock">
                                <Setter Property="FontSize" Value="30"/>
                                <Style.Triggers>
                                    <Trigger Property="IsMouseOver" Value="True">
                                        <Setter Property="FontSize" Value="50"/>
                                        <Setter Property="Foreground" Value="Red"/>
                                    </Trigger>
                                </Style.Triggers>
                            </Style>
                        </Grid.Resources>
                        <Image Source="{Binding ImgUrl,Converter={StaticResource ImgConverter}}"
                                   Stretch="Uniform"
                                   Grid.Row="0"
                                   Grid.RowSpan="2"
                                   Grid.Column="0"
                                   Grid.ColumnSpan="2"/>
                        <TextBlock Text="{Binding Id}" Grid.Row="0" Grid.Column="0"/>
                        <TextBlock Text="{Binding Name}" Grid.Row="0" Grid.Column="1"/>
                        <TextBlock Text="{Binding ISBN}" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2"/>
                    </Grid>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </Grid>
</Window>
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Globalization;
using System.IO;
using System.Runtime.CompilerServices;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp12
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
    }

    public class MainVM : INotifyPropertyChanged
    {
        private DateTime startTime;
        public MainVM()
        {
            Task.Run(async () =>
            {
                await InitBooksCollection(52600000);
            });
        }
        public async Task InitBooksCollection(int cnt = 100000)
        {
            BooksCollection = new ObservableCollection<Book>();
            List<Book> booksList = new List<Book>();
            var imgDir = @"../../../Images";
            if (!Directory.Exists(imgDir))
            {
                return;
            }
            var imgs = Directory.GetFiles(imgDir);
            if (imgs == null || !imgs.Any())
            {
                return;
            }
            int imgsCount = imgs.Count();

            startTime = DateTime.Now;
            for (int i = 1; i < cnt + 1; i++)
            {
                booksList.Add(new Book()
                {
                    Id = i,
                    Name = $"Name_{i}",
                    ISBN = $"ISBN_{i}_{Guid.NewGuid():N}",
                    ImgUrl = $"{imgs[i % imgsCount]}"
                });

                if (i < 1000 && i % 200 == 0)
                {
                    await PopulateBooksCollectionAsync(booksList);
                    await Task.Delay(1);
                }

                else if (i % 1000000 == 0)
                {
                    await PopulateBooksCollectionAsync(booksList);
                    await Task.Delay(1);
                }
            }

            if (booksList.Any())
            {
                await PopulateBooksCollectionAsync(booksList);
            }
        }

        private async Task PopulateBooksCollectionAsync(List<Book> booksList)
        {
            var tempList = booksList.ToList();
            await Application.Current.Dispatcher.InvokeAsync(() =>
            {
                foreach (var bk in tempList)
                {
                    BooksCollection.Add(bk);
                }
                MainTitle = $"{DateTime.Now},loaded {BooksCollection.Count} items,{GetMem()},{GetTimeCost()}";
                booksList.Clear();
            }, System.Windows.Threading.DispatcherPriority.Background);
        }

        public string GetTimeCost()
        {
            var dtSpan = DateTime.Now.Subtract(startTime);
            return $"Time cost {dtSpan.TotalSeconds:0.00} seconds";
        }

        private string GetMem()
        {
            return $"{System.Diagnostics.Process.GetCurrentProcess().PrivateMemorySize64 / 1024 / 1024:N2} M";
        }

        private string mainTitle = "";
        public string MainTitle
        {
            get
            {
                return mainTitle;
            }
            set
            {
                if (value != mainTitle)
                {
                    mainTitle = value;
                    OnPropertyChanged();
                }
            }
        }

        private ObservableCollection<Book> booksCollection;
        public ObservableCollection<Book> BooksCollection
        {
            get
            {
                return booksCollection;
            }
            set
            {
                if (value != booksCollection)
                {
                    booksCollection = value;
                    OnPropertyChanged();
                }
            }
        }

        public event PropertyChangedEventHandler? PropertyChanged;
        private void OnPropertyChanged([CallerMemberName] string propertyName = "")
        {
            var handler = PropertyChanged;
            handler?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }

    public class ImgConverter : IValueConverter
    {
        private Dictionary<string, ImageSource> imgCache = new Dictionary<string, ImageSource>();
        private readonly object objLock = new object();
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            var imgUrl = value?.ToString();
            if (string.IsNullOrWhiteSpace(imgUrl) || !File.Exists(imgUrl))
            {
                return null;
            }

            lock (objLock)
            {
                if (imgCache.ContainsKey(imgUrl))
                {
                    return imgCache[imgUrl];
                }

                BitmapImage bmi = new BitmapImage();
                bmi.BeginInit();
                bmi.UriSource = new Uri(imgUrl, UriKind.RelativeOrAbsolute);
                //bmi.DecodePixelWidth = 1200;
                //bmi.DecodePixelHeight = 700;
                bmi.CacheOption = BitmapCacheOption.OnLoad;
                bmi.EndInit();
                if (bmi.CanFreeze)
                {
                    bmi.Freeze();
                }
                imgCache[imgUrl] = bmi;
                return bmi;
            }
            return null;
        }


        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            return DependencyProperty.UnsetValue;
        }
    }


    public class DelCommand : ICommand
    {
        private Action<object?>? execute;
        private Predicate<object?>? canExecute;
        public DelCommand(Action<object?>? executeValue, Predicate<object?>? canExecuteValue = null)
        {
            execute = executeValue;
            canExecute = canExecuteValue;
        }

        public event EventHandler? CanExecuteChanged
        {
            add
            {
                CommandManager.RequerySuggested += value;
            }
            remove
            {
                CommandManager.RequerySuggested -= value;
            }
        }

        public bool CanExecute(object? parameter)
        {
            return canExecute == null ? true : canExecute(parameter);
        }

        public void Execute(object? parameter)
        {
            execute?.Invoke(parameter);
        }
    }


    public class Book
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string ISBN { get; set; }
        public string ImgUrl { get; set; }
    }

}

image

image

image