如何截取scrollView里面的图片

如下

- (UIImage *)captureScrollView:(UIScrollView *)scrollView{
UIImage* image = nil;
UIGraphicsBeginImageContext(scrollView.contentSize);
{
CGPoint savedContentOffset = scrollView.contentOffset;
CGRect savedFrame = scrollView.frame;
scrollView.contentOffset = CGPointZero;
scrollView.frame = CGRectMake(0, 0, scrollView.contentSize.width, scrollView.contentSize.height);

[scrollView.layer renderInContext: UIGraphicsGetCurrentContext()];
image = UIGraphicsGetImageFromCurrentImageContext();

scrollView.contentOffset = savedContentOffset;
scrollView.frame = savedFrame;
}
UIGraphicsEndImageContext();

if (image != nil) {
return image;
}
return nil;
}