Class POINT ... PointToClient ,,,, which reference should i use .... please advise...

[cielle]

please helppppssss....



i m using this for listbox double click event...

Point p = Cursor.Position;
p = ListBox1.PointToClient(p);
if (ListBox1.IndexFromPoint(p) != -1)
{
}



but i have no idea which reference i missed to declare.

i m using microsoft Visual Studio c#



please advise me which reference i should add...



i have googled and tried all possible reference... but stilll doesn;t solve the problem...







MANY THANKS!!1