iOS切圆形图片

/** 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;  

}