如果你以某种方式改变scrollView contentSize(例如，添加一些东西到stackView是在scrollView)，你必须调用scrollView. layoutifneeded()在滚动之前，否则它什么都不做。

例子:

scrollView.layoutIfNeeded()
let bottomOffset = CGPoint(x: 0, y: scrollView.contentSize.height - scrollView.bounds.size.height + scrollView.contentInset.bottom)
if(bottomOffset.y > 0) {
    scrollView.setContentOffset(bottomOffset, animated: true)
}

迅速:

你可以使用这样的扩展:

extension UIScrollView {
    func scrollsToBottom(animated: Bool) {
        let bottomOffset = CGPoint(x: 0, y: contentSize.height - bounds.size.height)
        setContentOffset(bottomOffset, animated: animated)
    }
}

Use:

scrollView.scrollsToBottom(animated: true)

如果你不需要动画，这是可行的:

[self.scrollView setContentOffset:CGPointMake(0, CGFLOAT_MAX) animated:NO];

滚动到顶部

- CGPoint topOffset = CGPointMake(0, 0);
- [scrollView setContentOffset:topOffset animated:YES];

滚动到底部

- CGPoint bottomOffset = CGPointMake(0, scrollView.contentSize.height - self.scrollView.bounds.size.height);
 - [scrollView setContentOffset:bottomOffset animated:YES];

Swift 2.2解决方案，考虑了contentInset

let bottomOffset = CGPoint(x: 0, y: scrollView.contentSize.height - scrollView.bounds.size.height + scrollView.contentInset.bottom)
scrollView.setContentOffset(bottomOffset, animated: true)

这应该是一个扩展

extension UIScrollView {

  func scrollToBottom() {
    let bottomOffset = CGPoint(x: 0, y: contentSize.height - bounds.size.height + contentInset.bottom)
    setContentOffset(bottomOffset, animated: true)
  }
}

注意，您可能想检查bottomOffset。滚动前的Y > 0

看起来这里所有的答案都没有考虑到安全区域。 从iOS 11开始，iPhone X引入了安全区域。这可能会影响scrollView的contentInset。

对于iOS 11及以上版本，正确地滚动到底部，包括插入的内容。你应该使用adjustedContentInset而不是contentInset。检查这段代码:

迅速:

let bottomOffset = CGPoint(x: 0, y: scrollView.contentSize.height - scrollView.bounds.height + scrollView.adjustedContentInset.bottom)
scrollView.setContentOffset(bottomOffset, animated: true)

objective - c

CGPoint bottomOffset = CGPointMake(0, self.scrollView.contentSize.height - self.scrollView.bounds.size.height + self.scrollView.adjustedContentInset.bottom);
[self.scrollView setContentOffset:bottomOffset animated:YES];

Swift扩展(这保留了原来的contenttoffset .x):

extension UIScrollView {
    func scrollsToBottom(animated: Bool) {
        let bottomOffset = CGPoint(x: contentOffset.x,
                                   y: contentSize.height - bounds.height + adjustedContentInset.bottom)
        setContentOffset(bottomOffset, animated: animated)
    }
}

引用:

adjustedContentInset