ViewController.h 需要實現

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

- (void)sendMessage:(void(^)(NSString *))blc;

@end

ViewController.m裡面需要實現

#import "ViewController.h"

#import "secondeViewController.h"

@interface ViewController ()

{

void (^tempBloc)(NSString

UITextField *textField;

}

@end

@implementation ViewController

- (void)viewDidLoad {

    [superviewDidLoad];

UIButton *button = [UIButtonnew];

    button.backgroundColor = [UIColorredColor];

    button.frame = CGRectMake(100, 100, 50, 50);

    [button addTarget:selfaction:@selector(gotoSecondeViewController)

    [self.viewaddSubview:button];

textField = [UITextFieldnew];

textField.frame = CGRectMake(100, 300, 200, 50);

    [self.viewaddSubview:textField];

}

- (void)gotoSecondeViewController{

    secondeViewController *KsecondeViewController = [secondeViewController

    KsecondeViewController.VC = self;

    [selfpresentViewController:KsecondeViewController animated:YEScompletion:^{

    }];

if (tempBloc) {

tempBloc(textField.text);

    }

}

- (void)sendMessage:(void (^)(NSString *))blc{

tempBloc = ^(NSString *str){

        blc(str);

    };

}

secondeViewController.h裡面需要實現

#import <UIKit/UIKit.h>

#import "ViewController.h"

@interface secondeViewController : UIViewController

@property (nonatomic,strong)ViewController *VC;

@end

secondeViewController.m裡面需要實現

#import "secondeViewController.h"

#import "ViewController.h"

@interface secondeViewController ()

@end

@implementation secondeViewController

- (void)viewDidLoad {

    [superviewDidLoad];

self.view.backgroundColor = [UIColorwhiteColor];

UILabel *lable = [UILabelnew];

    lable.backgroundColor = [UIColorgreenColor];

    lable.frame = CGRectMake(100, 100, 200, 50);

    [self.viewaddSubview:lable];

    [_VC sendMessage:^(NSString *str) {

        lable.text = str;

    }];    

}