Question

In my code below, I’m showing a context menu when the user right-clicks on a cell in my DataGridView. I’d also like the cell that the user right-clicks on to change background color so that they can see the cell they’ve “right-click selected”. Is there a way to add something to my code below so that this occurs?

private void dataGridView2_MouseClick(object sender, MouseEventArgs e)
    {
        if (e.Button == MouseButtons.Right)
        {
            ContextMenu m = new ContextMenu();
            MenuItem mnuCopy = new MenuItem("Copy");
            mnuCopy.Click += new EventHandler(mnuCopy_Click);
            m.MenuItems.Add(mnuCopy);

            int currentMouseOverRow = dataGridView2.HitTest(e.X, e.Y).RowIndex;               

            m.Show(dataGridView2, new Point(e.X, e.Y));

        }
    }

Answer 1

So obviously you’ve hacked into my workstation and have seen some of the stuff I’ve worked on recently. I exaggerate a bit because I didn’t do exactly what you’re trying to do but with a little bit of tweaking I was able to.

I would modify your MouseClick event to get the DGV’s CurrentCell. Once you have it, set the CurrentCell‘s Style property with the SelectionBackColor you want. Something like this:

// ...
DataGridView.HitTestInfo hti = dataGridView2.HitTest(e.X, e.Y);
if (hti.Type == DataGridViewHitTestType.Cell) {
    dataGridView2.CurrentCell = dataGridView2.Rows[hti.RowIndex].Cells[hti.ColumnIndex];
    dataGridView2.CurrentCell.Style = new DataGridViewCellStyle { SelectionBackColor = System.Drawing.Color.Yellow};
}
//...

The above is a bit ‘air code-y’ (in other words I haven’t attempted to merge it with your code and run it) but I hope you get the idea. Notice that I check through the hit test that a cell was clicked; if you don’t do this and the user does not click a cell you might have some problems.

Now there’s the problem that this code will change the SelectionBackColor for the all the cells you right click. That’s easy to restore this property in the DGV’s CellLeave event:

private void dgvBatches_CellLeave(object sender, DataGridViewCellEventArgs e) {
    dataGridView2.CurrentCell.Style = new DataGridViewCellStyle { SelectionBackColor = System.Drawing.SystemColors.Highlight };
}

I’ll have to remember this visual affect; thanks for asking the question.