You can use the CellMouseEnter and CellMouseLeave to track the row number that the mouse is currently hovering over.
Then use a ContextMenu object to display you popup menu, customised for the current row.
Here’s a quick and dirty example of what I mean…
private void dataGridView1_MouseClick(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Right)
{
ContextMenu m = new ContextMenu();
m.MenuItems.Add(new MenuItem("Cut"));
m.MenuItems.Add(new MenuItem("Copy"));
m.MenuItems.Add(new MenuItem("Paste"));
int currentMouseOverRow = dataGridView1.HitTest(e.X,e.Y).RowIndex;
if (currentMouseOverRow >= 0)
{
m.MenuItems.Add(new MenuItem(string.Format("Do something to row {0}", currentMouseOverRow.ToString())));
}
m.Show(dataGridView1, new Point(e.X, e.Y));
}
}