When I try to cast the DataGrid.ItemsSource to the DataView for the second time, I get an error ("Unable to cast object...")

Question

I will give two credits to anyone who answers this question by submitting the output (I have two accounts).
If my country's banks were not sanctioned, I would give a gift to the individual who answered this question (I've been looking for an acceptable response for months).

I want the rows that the user selects to be deleted.
As far as I know, the DataGrid.ItemsSource cannot be removed directly using the DataGrid.Items.Remove() method, so I must convert the DataGrid.ItemsSource to a DataTable and use the DataGrid.ItemsSource = DataTable.DefaultView property.
To convert DataGrid.ItemsSource to DataTable, I tried the following solutions in various situations, and each has advantages and disadvantages (I spent several months researching and testing):

First solution (I made this by myself):
XAML:

C#:

    public byte[] ImageSourceToBytes(BitmapEncoder BitEncoder, ImageSource ImgSource)  
    {  
        byte[] Bytes = null;  
        switch ((ImgSource as BitmapSource) != null)  
        {  
            case true:  
                BitEncoder.Frames.Add(BitmapFrame.Create((ImgSource as BitmapSource)));  
                using (var Stream = new System.IO.MemoryStream())  
                {  
                    BitEncoder.Save(Stream);  
                    Bytes = Stream.ToArray();  
                }  
                break;  
        }  
        return Bytes;  
    }  
    public DataTable DataGridToDataTable(DataGrid DG, DataTable DT, byte NumberOfColumns, byte VisualColumnIndex, string ControlName)  
    {  
        for (int i = 0; i < DG.Items.Count; i++)  
        {  
            DT.Rows.Add(DG.Items[i]);  
        }  
        for (int i = 0; i < DG.Items.Count; i++)  
        {  
            for (byte j = 0; j < NumberOfColumns; j++)  
            {  
                switch (j == VisualColumnIndex)  
                {  
                    case true:  
                        FrameworkElement FE = DG.Columns[j].GetCellContent((DataGridRow)DG.ItemContainerGenerator.ContainerFromIndex(i));  
                        Image Img = new Image() { Source = ((((DataGridTemplateColumn)DG.Columns[j]).CellTemplate.FindName(ControlName, FE) as Image).Source) };  
                        DT.Rows[i][j] = ImageSourceToBytes(new PngBitmapEncoder(), Img.Source);  
                        break;  
                    default:  
                        DG.ScrollIntoView((DataRowView)DG.Items[i]);  
                        DT.Rows[i][j] = ((DG.Columns[j].GetCellContent(((DataGridRow)DG.ItemContainerGenerator.ContainerFromIndex(i)))) as TextBlock).Text;  
                        break;  
                }  
            }  
        }  
        return DT;  
    }

Advantage: Even if one of the columns is of the Image type, this approach operates without an error.
Disadvantage: The method DG.ScrollIntoView((DataRowView)DG.Items[i]) must be used when the EnableRowVirtualization attribute is set to True; otherwise, a null error will occur. For large numbers of rows, this approach is incredibly sluggish (e.g., if we have 20,000 rows, it could take an hour or more).

Second solution (I made this by myself):
XAML:

C#:

    public DataTable DataGridToDataTable(DataGrid DG, DataTable DT, byte NumberOfColumns, byte VisualColumnIndex, string ControlName)  
    {  
        for (int i = 0; i < DG.Items.Count; i++)  
        {  
            DT.Rows.Add(DG.Items[i]);  
        }  
        for (int i = 0; i < DG.Items.Count; i++)  
        {  
            for (byte j = 0; j < NumberOfColumns; j++)  
            {  
                switch (j == VisualColumnIndex)  
                {  
                    case true:  
                        FrameworkElement FE = DG.Columns[j].GetCellContent((DataGridRow)DG.ItemContainerGenerator.ContainerFromIndex(i));  
                        Image Img = new Image() { Source = ((((DataGridTemplateColumn)DG.Columns[j]).CellTemplate.FindName(ControlName, FE) as Image).Source) };  
                        DT.Rows[i][j] = ImageSourceToBytes(new PngBitmapEncoder(), Img.Source);  
                        break;  
                    default:  
                        DT.Rows[i][j] = ((DG.Columns[j].GetCellContent(((DataGridRow)DG.ItemContainerGenerator.ContainerFromIndex(i)))) as TextBlock).Text;  
                        break;  
                }  
            }  
        }  
        return DT;  
    }

Advantage: This solution converts DataGrid.ItemsSource to DataTable faster than the first because EnableRowVirtualization is equal to False in this case.
Disadvantage: This solution consumes a lot of memory; for example, if we have 100,000 rows and the database table is 2GB in size, it will consume 2GB of RAM and a RAM space error may occur.

Third solution:
XAML:

C#:

    uint[] BookCodeSelectedItems = null; //I need this for further calculations  
    private void DataGridDeleteMenu_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)  
    {  
        switch (BookDataGrid.SelectedItems.Count > 0)  
        {  
            case true:  
                List

Accepted Answer

Finally, I found a solution that does not have the above problems.
I made a strategic mistake. When we connect DataGrid.ItemsSource to DataView or CollectionViewSource.Source for the first time, the values of DataView and CollectionViewSource.Source change automatically with each change (like insert, edit, and delete), so the code that connects DataGrid.ItemsSource to DataView or CollectionViewSource does not need to be rewritten.

Look carefully at the image below to get a better understanding of how this feature works. When DataGrid.ItemsSource changes in the first window, DataGrid.ItemsSource in the second window also changes.

I tested the following codes in different situations, using nearly the entire capacity of the MS Access database.

The conditions are as follows:

Number of records = 252,500

Database size = 2,094,128 KB (database size without any rows = 604 KB)

Size of each row = (Database size - database size without any rows) / Number of records => about 8.291184 KB (Of course, if I haven't made a mistake)

Hardware and software used in the test = Acer Aspire 5750G Laptop (Core i5 2nd Gen/4 GB RAM/Win7-x64), Visual Studio 2017, .NET Framework 4.5.2, WPF

XAML:

C#:

public DataView BDV = new DataView();  
object[] BookCodeSelectedItems = null;  
object[] ISBN_Value = null;  
public MainWindow()  
{  
    InitializeComponent();  
    BDV = BookDataGrid.ItemsSource as DataView; //In "XAML" or "C#," binding is only necessary once  
}  
private void DataGridDeleteMenu_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)  
{  
    switch (BookDataGrid.SelectedItems.Count > 0)  
    {  
        case false:  
            MessageWindow MW = new MessageWindow();  
            MW.YesButton.Visibility = Visibility.Hidden;  
            MW.NoButton.Visibility = Visibility.Hidden;  
            MW.MessageLabel.Margin = new Thickness(0, 110, 0, 0);  
            MW.MessageLabel.HorizontalAlignment = HorizontalAlignment.Center;  
            MW.Image.Source = GetImageFromBytes(System.IO.File.ReadAllBytes(System.Windows.Forms.Application.StartupPath + @"\Images\Warning.bin"));  
            MW.MessageTextBlock.Text = "No rows selected";  
            MW.OKButton.Content = "OK";  
            MW.ShowDialog();  
            break;  
        default:  
            var stopwatch = new System.Diagnostics.Stopwatch();  
            stopwatch.Start();  
            List

When I try to cast the DataGrid.ItemsSource to the DataView for the second time, I get an error ("Unable to cast object...")

0 additional answers