UIBezierPath*maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds byRoundingCorners:(UIRectCornerTopRight | UIRectCornerBottomRight) cornerRadii:CGSizeMake(7.5,7.5)];//圆角大小
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
maskLayer.frame = view.bounds;
maskLayer.path = maskPath.CGPath;
view.layer.mask = maskLayer;
}
(UIRectCornerTopRight | UIRectCornerBottomRight) 这个控制圆角的位置