DataGridView multiselect without CTRL

One of my mates has asked my about how to enable a datagridview multiselection without pressing CTRL key (for a touch screen). I haven't tested it throughly, but here comes a (C#) possible solution:

I´ve tested it only with a Datagridview configured for full row selection.

Basically I hold a private collection of the rows I want to select and every time a row is pressed, it´s selected or removed accordingly

The empty override method avoids selection refresh. Try to remove it and see...

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Collections;
using System.Diagnostics;

namespace MyDataGridView
{
public partial class MyDataGridV : DataGridView
{
private Hashtable mySelectedRows = new Hashtable();

public MyDataGridV()
{

}

protected override void OnCellMouseDown(DataGridViewCellMouseEventArgs e)
{

}

protected override void OnCellClick(DataGridViewCellEventArgs e)
{
if (mySelectedRows.ContainsKey(e.RowIndex))
{
mySelectedRows.Remove(e.RowIndex);
}
else
{
mySelectedRows.Add(e.RowIndex, this.Rows[e.RowIndex]);
}
for (int i = 0; i < this.Rows.Count; i++)
{
if (mySelectedRows.Contains(i))
{
this.SetSelectedRowCore(i, true);
}
else
{
this.SetSelectedRowCore(i, false);
}
}
Debug.Assert(this.SelectedRows.Count == mySelectedRows.Count, "Selected rows number don´t match");
base.OnCellClick(e);
}


}
}