HScrollBar keeps accumulating value after a reset of its value - winforms

Question

Lets say you have an HScrollBar. Also lets say you might want to cancel scrolling and return to a previous value. You are at scroll bar value of 3 for example. Now a user clicks on the scroll bar to advance one value (largechange and smallchange are both set to 1). You handle the scroll event as follows:
// Global sheet number containing current sheet number
int sheetNum;
private void hsbSheet_Scroll(object sender, ScrollEventArgs e)
{
// Process only the EndScroll Event
if (e.Type == ScrollEventType.EndScroll)
{
// Validation
if (!checkValidation())
{
// Rollback Scroll Value
hsbSheet.Value = sheetNum;
hsbSheet.Update();
// Exit
return;
}
// Process Scroll
processScroll();
}
}
If there is a validation error, the scroll value goes back to the previous value. In this example, user was trying to set value of scroll bar to 4. But since there was a validation error, scroll value is back at 3 again. Now if he clicks on the scroll bar again, the value is now 5! Now here comes my question, how do you stop the value from accumulating that way after having been reset back to 3? In another words, when he clicks on the scroll bar again to increment, it should have been 4 again.
Thanks before hand.
Update #1
I am trying everything:
...
// Rollback Scroll Value
hsbSheet.Value = sheetNum;
hsbSheet.Refresh();
hsbSheet.ResetText();
hsbSheet.Update();
...
And it still has the same issue...

Answer 1

hsbSheet.Value = sheetNum;
You cannot update the Value property in the Scroll event handler, it will very quickly be overwritten again when the event handler returns. You are supposed to use the e.NewValue property to override where it is going to go. Like this:
if (!checkValidation())
{
e.NewValue = sheetNum; // or e.OldValue
return;
}