iOS 屏幕截取

1.截取特定view

- (UIImage*)screenView:(UIView *)view{
    if(&UIGraphicsBeginImageContextWithOptions != NULL)
    {
        UIGraphicsBeginImageContextWithOptions(view.frame.size, NO, 0.0);
    } else {
        UIGraphicsBeginImageContext(view.frame.size);
    }
    [view.layer renderInContext:UIGraphicsGetCurrentContext()];
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;
}

2.截取scrollView的所有，包括下面没显示的（UITabelview，UIWebView类似）

- (UIImage*)getCapture
{
    
    UIImage* viewImage = nil;
    UIScrollView *scrollView = self.webView.scrollView;
    UIGraphicsBeginImageContextWithOptions(scrollView.contentSize, scrollView.opaque, 0.0);
    {
        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()];
        viewImage = UIGraphicsGetImageFromCurrentImageContext();
        
        scrollView.contentOffset = savedContentOffset;
        scrollView.frame = savedFrame;
    }
    UIGraphicsEndImageContext();
    
    return viewImage;
}