iOS ViewController之间传值方法五(使用block)

5.使用block在ViewController之间传值

在B页面

.h文件

@interface TwoViewController : UIViewController

//定义一个block，参数为字符串

typedef void (^ablock)(NSString *str);

@property (nonatomic,copy)ablock block;

//自定义的NSString

@property (nonatomic,weak)NSString *nameStr;

@end

.m文件 点击事件里面给block传值

-(void)click{

    if (self.block) {

        self.block(_nameStr);

        [selfdismissViewControllerAnimated:YEScompletion:nil];

    }

}

在A页面

.m文件 回调block

TwoViewController *vc = [[TwoViewControlleralloc]init];

    [selfpresentViewController:vc animated:YEScompletion:nil];

    vc.block = ^(NSString *str){

        newLabel.text = str;

        NSLog(@"66666666666666666 %@",newLabel.text);

    };