AddonHelper.FormDrag.WndProc C# (CSharp) Méthode

        protected override void WndProc(ref Message m)
        {
            if (m.Msg == 0x20a) { // WM_VSCROLL
                if (this.ScreenBox.Visible) {
                    if (m.WParam.ToInt32() < 0) { // Scroll down
                        this.ScalePercentage -= 4;
                        if (this.ScalePercentage < 1)
                            this.ScalePercentage = 1;
                    } else { // Scroll up
                        this.ScalePercentage += 4;
                        if (this.ScalePercentage > 100)
                            this.ScalePercentage = 100;
                    }

                    this.ScreenBox.Text = this.ScalePercentage + "%";
                }
            }

            base.WndProc(ref m);
        }