生成圆角的图片

/**

• 生成圆角的图片
• @param originImage 原始图片
• @param borderColor 边框原色
• @param borderWidth 边框宽度
• @return 圆形图片
  */

• (UIImage *)circleImage:(UIImage *)originImage borderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth
  {
  //设置边框宽度
  CGFloat imageWH = originImage.size.width;

  //计算外圆的尺寸
  CGFloat ovalWH = imageWH + 2 * borderWidth;

  //开启上下文
  UIGraphicsBeginImageContextWithOptions(originImage.size, NO, 0);

  //画一个大的圆形
  UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(0, 0, ovalWH, ovalWH)];

  [borderColor set];

  [path fill];

  //设置裁剪区域
  UIBezierPath *clipPath = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(borderWidth, borderWidth, imageWH, imageWH)];
  [clipPath addClip];

  //绘制图片
  [originImage drawAtPoint:CGPointMake(borderWidth, borderWidth)];

  //从上下文中获取图片
  UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();

  //关闭上下文
  UIGraphicsEndImageContext();
  return resultImage;
  }