使用以下代码：

scrollView.contentOffset = CGPoint(x: 0, y: 0)

要设置滚动的动画，请执行以下操作：

CGRect frame = CGRectMake(0, 768, 1024, 748); //wherever you want to scroll 
[self.scrollView scrollRectToVisible:frame animated:YES];

最简单的动画方式->

[scrollView setContentOffset:CGPointMake(0, 0) animated:YES]

Swift 3版本的答案是：
scrollView.contentOffset = CGPoint(x: 0.0, y: 0.0)

如果有人想知道如何在Swift 5中使用xcode 11实现它：
我在x参数中设置了负值，因为我想向左滚动

let frame = CGRect(x: -540, y: 0, width: 1080, height: 370); //wherever you want to scroll
boardScrollView.scrollRectToVisible(frame, animated: true) // set animated to true if you want to animate it

override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        scrollView.setContentOffset(CGPoint(x: 0.0, y: 350.0), animated: true)
    }