我们给一个View设置圆角一般都是用如下代码
// 设置layer超出父图层的部分剪切掉
self.cornerView.layer.masksToBounds = YES;
// 设置圆角半径，若imageView1为正方形，设置圆角半径为边长的一半可实现圆效果
self.cornerView.layer.cornerRadius = 20.0;
但是如果需求是只要左上和右上圆角以上方法肯定不能实现,直接上代码
UIBezierPath *bezierPath = [UIBezierPath bezierPathWithRoundedRect:self.cornerView.bounds byRoundingCorners:UIRectCornerTopLeft | UIRectCornerTopRight cornerRadii:(CGSize){20.0}];
CAShapeLayer *shapeLayer = [CAShapeLayer layer];
// 设置绘制路径
shapeLayer.path = bezierPath.CGPath;
// 将shapeLayer设置为cornerView的layer的mask
self.cornerView.layer.mask = shapeLayer;
实现四个圆角
// 绘制4个角，
UIBezierPath *bezierPath = [UIBezierPath bezierPathWithRoundedRect:self.cornerView.bounds cornerRadius:20.0];
CAShapeLayer *shapeLayer = [CAShapeLayer layer];
// 设置绘制路径
shapeLayer.path = bezierPath.CGPath;
self.cornerView.layer.mask = shapeLayer;
