定义：
pageControl = [[[UIPageControl alloc]initWithFrame:CGRectMake(300, 200, 100, 30)]autorelease];//定义初始化
[pageControl setNumberOfPages:9];//设置总页数
[pageControl setCurrentPage:0];//设置当前页
[pageControl addTarget:self action:@selector(clickpagecontrol) forControlEvents:UIControlEventValueChanged];//添加事件
[self.view addSubview:pageControl];//这个就不解释啦
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView1
//减速停止的时候执行，如果没有这个方法慢慢拖动的时候，会导致 offsetofScrollView.x / scroll.frame.size.width 计算不准确 ，
{
CGPoint offsetofScrollView = scrollView1.contentOffset;
[pageControl setCurrentPage:offsetofScrollView.x / scroll.frame.size.width];
}
-(void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
//停止拖拽的时候开始执行，如果没有这个方法 你会发现当你快速滑动UIScrollview的时候并没有触发scrollViewDidEndDecelerating:(UIScrollView *)scrollView1事件
{
CGPoint offsetofScrollView = scroll.contentOffset;
[pageControl setCurrentPage:offsetofScrollView.x / scroll.frame.size.width];
}
-(void)clickpagecontrol
{//点击UIPageControl 出发的事件
[scroll scrollRectToVisible:CGRectMake(pageControl.currentPage*scroll.frame.size.width, 0, scroll.frame.size.width , scroll.frame.size.height) animated:YES];
}