Valdyr，希望这对你有帮助

CGPoint bottomOffset = CGPointMake(0, [textView contentSize].height - textView.frame.size.height);

if (bottomOffset.y > 0)
 [textView setContentOffset: bottomOffset animated: YES];

CGFloat yOffset = scrollView.contentOffset.y;

CGFloat height = scrollView.frame.size.height;

CGFloat contentHeight = scrollView.contentSize.height;

CGFloat distance = (contentHeight  - height) - yOffset;

if(distance < 0)
{
    return ;
}

CGPoint offset = scrollView.contentOffset;

offset.y += distance;

[scrollView setContentOffset:offset animated:YES];

快速执行:

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

使用它:

yourScrollview.scrollToBottom(animated: true)

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];

扩展UIScrollView添加一个scrollToBottom方法:

extension UIScrollView {
    func scrollToBottom(animated:Bool) {
        let offset = self.contentSize.height - self.visibleSize.height
        if offset > self.contentOffset.y {
            self.setContentOffset(CGPoint(x: 0, y: offset), animated: animated)
        }
    }
}

迅速:

   if self.mainScroll.contentSize.height > self.mainScroll.bounds.size.height {
        let bottomOffset = CGPointMake(0, self.mainScroll.contentSize.height - self.mainScroll.bounds.size.height);
        self.mainScroll.setContentOffset(bottomOffset, animated: true)
    }