VixenModules.App.Curves.CurveEditor.zedGraphControl_MouseDownEvent C# (CSharp) Méthode

        private bool zedGraphControl_MouseDownEvent(ZedGraphControl sender, MouseEventArgs e)
        {
            if (ReadonlyCurve)
                return false;

            CurveItem curve;
            int dragPointIndex;

            // if CTRL is pressed, and we're not near a specific point, add a new point
            if (Control.ModifierKeys.HasFlag(Keys.Control) &&
                !zedGraphControl.GraphPane.FindNearestPoint(e.Location, out curve, out dragPointIndex)) {
                // only add if we've actually clicked on the pane, so make sure the mouse is over it first
                if (zedGraphControl.MasterPane.FindPane(e.Location) != null) {
                    PointPairList pointList = zedGraphControl.GraphPane.CurveList[0].Points as PointPairList;
                    double newX, newY;
                    zedGraphControl.GraphPane.ReverseTransform(e.Location, out newX, out newY);
                    //Verify the point is in the usable bounds.
                    if (newX > 100)
                    {
                        newX = 100;
                    }
                    else if(newX < 0)
                    {
                        newX = 0;
                    }
                    if (newY > 100)
                    {
                        newY = 100;
                    }
                    else if (newY < 0)
                    {
                        newY = 0;
                    }
                    pointList.Insert(0, newX, newY);
                    pointList.Sort();
                    zedGraphControl.Invalidate();
                }
            }
            // if the ALT key was pressed, and we're near a point, delete it -- but only if there would be at least two points left
            if (Control.ModifierKeys.HasFlag(Keys.Alt) &&
                zedGraphControl.GraphPane.FindNearestPoint(e.Location, out curve, out dragPointIndex)) {
                PointPairList pointList = zedGraphControl.GraphPane.CurveList[0].Points as PointPairList;
                if (pointList.Count > 2) {
                    pointList.RemoveAt(dragPointIndex);
                    pointList.Sort();
                    zedGraphControl.Invalidate();
                }
            }

            if (!Curve.IsLibraryReference && e.Button == MouseButtons.Left && sender.DragEditingPair != null)
            {
                txtXValue.Text = sender.DragEditingPair.X.ToString();
                txtYValue.Text = sender.DragEditingPair.Y.ToString();
                txtXValue.Enabled = txtYValue.Enabled = btnUpdateCoordinates.Enabled = true;
            }

            return false;
        }