/// <summary>
/// Go to the previous "page"
/// </summary>
/// <returns>bool if this worked</returns>
public bool Previous()
{
var result = false;
ScrollInfo scrollInfoBefore;
var hasScrollInfo = TryRetrievePosition(out scrollInfoBefore);
switch (ScrollMode)
{
case ScrollModes.KeyboardPageUpDown:
result = InputGenerator.KeyPress(VirtualKeyCodes.PRIOR) == 2;
break;
case ScrollModes.WindowsMessage:
result = SendScrollMessage(ScrollBarCommands.SB_PAGEUP);
break;
case ScrollModes.AbsoluteWindowMessage:
if (!hasScrollInfo)
{
return(false);
}
// Calculate previous position, clone the scrollInfoBefore
var scrollInfoForPrevious = scrollInfoBefore;
scrollInfoForPrevious.Position = Math.Max(scrollInfoBefore.Minimum, scrollInfoBefore.Position - (int)scrollInfoBefore.PageSize);
result = ApplyPosition(ref scrollInfoForPrevious);
break;
case ScrollModes.MouseWheel:
var bounds = ScrollingWindow.GetInfo().Bounds;
var middlePoint = new NativePoint(bounds.X + bounds.Width / 2, bounds.Y + bounds.Height / 2);
result = InputGenerator.MoveMouseWheel(WheelDelta, middlePoint) == 1;
break;
}
return(result);
}