Swift weakSelf写法

类：AVC

#import

typedef void(^ABlock)(void);

@interface AVC : UIViewController

@property (nonatomic,copy) ABlock aBlock;

@end

引用类：

    @IBAction func btnClick(sender: AnyObject) {

        let vc:AVC = AVC()

        vc.aBlock = ({[weak self] in

            let vc0:AVC = AVC()

            self!.navigationController?.pushViewController(vc0, animated: true)

        })

        self.navigationController?.pushViewController(vc, animated: true)

    }