我們都知道iOS視圖圓角

[view.layer setCornerRadius:5];

但是某些需求上可能我們只需要指定View的某幾個角為圓角
例如：

素材001.png

圖中框出的橘色部分我們只需要左半塊圓角，這種要怎么實(shí)現(xiàn)呢

UIRectCorner rectCorner = UIRectCornerBottomLeft | UIRectCornerTopLeft;
//任意視圖
UIView *testView = [[UIView alloc] init];

UIBezierPath *bezierPath = [UIBezierPath bezierPathWithRoundedRect:testView.bounds byRoundingCorners:rectCorner cornerRadii:CGSizeMake(5, 5)];
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
maskLayer.frame = testView.bounds;
maskLayer.path = bezierPath.CGPath;
testView.layer.mask = maskLayer;

//UIRectCorner所有的值
typedef NS_OPTIONS(NSUInteger, UIRectCorner) {
    UIRectCornerTopLeft     = 1 << 0,
    UIRectCornerTopRight    = 1 << 1,
    UIRectCornerBottomLeft  = 1 << 2,
    UIRectCornerBottomRight = 1 << 3,
    UIRectCornerAllCorners  = ~0UL
};