iOS 设置圆形图片

/** 设置圆形图片(放到分类中使用) */
- (UIImage *)cutCircleImage 
{ 
UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0); 
// 获取上下文 
CGContextRef ctr = UIGraphicsGetCurrentContext(); 
// 设置圆形
 CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
 CGContextAddEllipseInRect(ctr, rect); 
// 裁剪
 CGContextClip(ctr); 
// 将图片画上去
 [self drawInRect:rect]; 
UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return image;
}