ios 指定角度圆角

 // 指定角度圆角

    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:_viewBackground.bounds byRoundingCorners:UIRectCornerTopLeft | UIRectCornerTopRight cornerRadii:CGSizeMake(10, 10)];

    CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];

    maskLayer.frame = _viewBackground.bounds;

    maskLayer.path = maskPath.CGPath;

    _viewBackground.layer.mask = maskLayer;