Two-way data binding of int[] or List<int> to DataGridView in WinForms

Question

This solution helps to populate dgv but since anonymous types are immutable such grid cannot be edited but even otherwise I dont't think it would have helped with 2-way binding

    List<int> values = GetValues();
    var dataGridView = new DataGridView();
    dataGridView.DataSource =  values.Select(el => new { Value = el }).ToList(); 

Using wrapper class allows me to edit cells but changes are not reflected on the original collection

    public class Wrapper<T>
    {
        public T Value { get; set; }
        public Wrapper(T value) => Value = value;
    }
    ...
    dataGridView.DataSource = new BindingList<Wrapper<int>>(values.Select(value => new Wrapper<int>(value)).ToList());

So how do you make it work?

Answer 1

Two-way databinding works based on change notification of the data source. Here your data source is List<int>, neither List<T> nor int raises change notification, thus two-way databinding doesn't make sense here.

Assuming you want to implement two-way databinding of BindingList<int> with DataGridView, here is what you can do:

BindingList<int> originalBindingList;
private void Form1_Load(object sender, EventArgs e)
{
    originalBindingList = new BindingList<int>(new List<int> { 1, 2, 3 });
    dataGridView1.DataSource = new ListDataSource<int>(originalBindingList);
}

Then:

• DataGridView will show you a Value column and rows containing the originalBindingList values.
• If you change values in DataGridView the values in originalBindingList will change.
• If you change values if originalBindingList in code, DataGridView will refresh values.

And here is ListDataSource:

public class ListDataSource<T> : BindingSource
{
    public ListDataSource(BindingList<T> original)
    {
        for (int i = 0; i < original.Count; i++)
        {
            this.Add(new Item(original, i));
        }
        original.ListChanged += (obj, args) =>
            this.OnListChanged(new ListChangedEventArgs(
                args.ListChangedType, args.NewIndex));
    }
    private class Item : INotifyPropertyChanged
    {
        IList<T> source;
        int index;
        public Item(IList<T> source, int index)
        {
            this.source = source;
            this.index = index;
        }
        public T Value
        {
            get { return source[index]; }
            set
            {
                source[index] = value;
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Value"));
            }
        }
        public event PropertyChangedEventHandler PropertyChanged;
    }
}