#pragma mark - 按钮的点击

- (IBAction)top {

    /*

    [UIView animateWithDuration:2.0 animations:^{

//        CGPoint offset = self.scrollView.contentOffset;

//        offset.y = 0;

//        self.scrollView.contentOffset = offset;

        self.scrollView.contentOffset = CGPointMake(self.scrollView.contentOffset.x, 0);

    }];

     */

    [self.scrollView setContentOffset:CGPointMake(self.scrollView.contentOffset.x, 0) animated:YES];

}