public Caret(TextArea textArea)
{
this.textArea = textArea;
textArea.GotFocus += new EventHandler(GotFocus);
textArea.LostFocus += new EventHandler(LostFocus);
if (Environment.OSVersion.Platform == PlatformID.Unix)
caretImplementation = new ManagedCaret(this);
else
caretImplementation = new Win32Caret(this);
}