How to disable horizontal scrolling of UIScrollView?

UPDATED: (After @EranMarom pointed out on his comment)

You can stop horizontal scrolling or vertical scrolling in the ScrollViewDelegate Method. Here it is how,

Stops Horizontal Scrolling:

If you want to scroll horizontally, then you need to increase the contentOffset.x. Preventing that stops the scrollview scroll in horizontal direction.

- (void)scrollViewDidScroll:(UIScrollView *)sender {
    sender.contentOffset.x = 0.0
}

Stops Vertical Scrolling:

If you want to scroll vertically, then you need to increase the contentOffset.y. Preventing that stops the scrollview scroll in vertical direction.

- (void)scrollViewDidScroll:(UIScrollView *)sender {
    sender.contentOffset.y = 0.0
}

Above code prevents the changes in x and y of a scrollview contentOffset and it leads to stop the scrolling in scrollViewDidScroll: method.

You have to set the contentSize property of the UIScrollView. For example, if your UIScrollView is 320 pixels wide (the width of the screen), then you could do this:

CGSize scrollableSize = CGSizeMake(320, myScrollableHeight);
[myScrollView setContentSize:scrollableSize];

The UIScrollView will then only scroll vertically, because it can already display everything horizontally.