Swift3.0block传值

浅谈swift3 的block传值&＃xff0c;有 a 界面跳到 b 界面&＃xff0c;然后再从 b 界面返回 a 界面&＃xff0c;同时 把 b 界面的数据用block传值传到 a 界面&＃xff1a;
a界面跳到b 界面的代码

func RightButtonClick() {let TagVC &＃61; TagViewController()TagVC.hidesBottomBarWhenPushed &＃61; trueTagVC.title &＃61; "标签"//block回传TagVC.switchoverCallblock &＃61; {(selectedArr,recommendArr,index) -> () inself.selectedArr &＃61; selectedArrself.recommendArr &＃61; recommendArrself.title &＃61; selectedArr[index]}self.navigationController?.pushViewController(TagVC, animated: true)}

b 界面回传a 界面 值&＃xff1a;
定义block

class TagViewController: UIViewController,UICollectionViewDataSource,UICollectionViewDelegate{//定义blockvar switchoverCallblock: ((_ selectedArr: [String], _ recommendArr: [String], _ index:Int) -> ())?var selectedArr &＃61; ["推荐","河北",""理财"]var recommendArr &＃61; ["有声","家居","育儿"]override func didReceiveMemoryWarning() {super.didReceiveMemoryWarning()// Dispose of any resources that can be recreated.}
}

回调传值

if switchoverCallblock !&＃61; nil {switchoverCallblock!(selectedArr,recommendArr,indexPath.item)_ &＃61; navigationController?.popViewController(animated: true)}

这就是简单的swift block传值