ios 指定角度圆角

 // 指定角度圆角

    UIBezierPath *maskPath = [UIBezierPathbezierPathWithRoundedRect:_viewBackground.boundsbyRoundingCorners:UIRectCornerTopLeft |UIRectCornerTopRight cornerRadii:CGSizeMake(10,10)];

    CAShapeLayer *maskLayer = [[CAShapeLayeralloc] init];

    maskLayer.frame =_viewBackground.bounds;

    maskLayer.path = maskPath.CGPath;

    _viewBackground.layer.mask = maskLayer;