Question

Here’s the code for my ListBox MouseMove event:

private void lbxItems_MouseMove(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left) //this one is good
    {
        lbxItems.DoDragDrop("Copy Text 1", DragDropEffects.Copy);
    }
    else if (Control.ModifierKeys == Keys.Alt && e.Button == MouseButtons.Left) //this desn't work
    {
        lbxItems.DoDragDrop("Copy Text 2", DragDropEffects.Copy);
    }
}

The e.Button == MouseButtons.Left condition alone works okay, but not with Control.ModifierKeys == Keys.Alt. I wonder if the ListBox control can recognize ALT key + Left Mousebutton combination. Can anyone suggest please?

Answer 1

Hmm, well, I think I found a fix here, which is pretty easy.

To make it work, I just need to evaluate the Control.ModifierKeys == Keys.Alt condition first and put e.Button == MouseButtons.Left in the else if statement. Thus, ALT + Left Mousebutton will always be checked first.

private void lbxItems_MouseMove(object sender, MouseEventArgs e)
{
    if (Control.ModifierKeys == Keys.Alt && e.Button == MouseButtons.Left) 
    {
        lbxItems.DoDragDrop("Copy Text 1", DragDropEffects.Copy);
    }
    else if (e.Button == MouseButtons.Left) 
    {
        lbxItems.DoDragDrop("Copy Text 2", DragDropEffects.Copy);
    }
}

Also, I have to point out that it’s not Control.ModifierKeys == Keys.Alt didn’t work, just the original code never got chance to run else if statement.