iOS UI-界面传值（三种方法）

 #import <Foundation/Foundation.h>

 @interface DataModel : NSObject

 @property (nonatomic, copy) NSString *name;
 @property (nonatomic, copy) NSString *address;

 @end

 #import "DataModel.h"

 @implementation DataModel

 @end

 #import <UIKit/UIKit.h>
 @class DataModel;
 //设置协议
 @protocol PassValueDelegate <NSObject>
 - (void) passValueFromFirstVCToSecondVC:(DataModel *) dataModel;
 @end

 @interface FirstViewController : UIViewController
 //设置代理
 @property (nonatomic, strong) id<PassValueDelegate> delegate;
 //设置通知传值接受者
 @property (nonatomic, strong) DataModel *firstNOtificationModel;
 //设置代理传值传值者
 @property (nonatomic, strong) DataModel *firstDelegateModel;

 @end

 #import "FirstViewController.h"
 #import "DataModel.h"
 #import "SecondViewController.h"

 @interface FirstViewController ()
 //设置接收通知传值的标签
 @property (nonatomic, strong)UILabel *label;
 //设置接收block传值的标签
 @property (nonatomic, strong)UILabel *lblBlock;

 @end

 @implementation FirstViewController

 - (void)viewDidLoad {
     [super viewDidLoad];
     [self.view setBackgroundColor:[UIColor orangeColor]];

     [self createButtonAndLabel];

     //创建观察者
     [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(receiveValue:) name:@"passValueFromSecondVCToFirstVC" object:nil];
 }

 #pragma mark - 创建按钮和标签
 - (void)createButtonAndLabel
 {
     //创建标签
     self.label = [[UILabel alloc] initWithFrame:CGRectMake(, , , )];
     [self.label setBackgroundColor:[UIColor redColor]];
     self.label.textAlignment = NSTextAlignmentCenter;
     [self.view addSubview:self.label];

     //创建标签
     self.lblBlock = [[UILabel alloc] initWithFrame:CGRectMake(, , , )];
     [self.lblBlock setBackgroundColor:[UIColor redColor]];
     self.lblBlock.textAlignment = NSTextAlignmentCenter;
     [self.view addSubview:self.lblBlock];

     //创建按钮
     UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
     [btn setFrame:CGRectMake(, , , )];
     [btn setBackgroundColor:[UIColor blackColor]];
     [btn setTitle:@"goToNextView" forState:UIControlStateNormal];
     [btn setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
     [btn addTarget:self action:@selector(goToNextView) forControlEvents:UIControlEventTouchUpInside];
     [self.view addSubview:btn];
 }

 #pragma mark - 观察者接收值关联方法
 - (void)receiveValue:(NSNotification *)notification
 {
     if ([notification.object isKindOfClass:[DataModel class]]) {
         self.firstNOtificationModel = notification.object;
         self.label.text = [NSString stringWithFormat:@"name:%@ address:%@",self.firstNOtificationModel.name,self.firstNOtificationModel.address];
     }
 }
 #pragma mark - 代理传值、block接收值
 //按钮关联方法
 - (void)goToNextView
 {
     SecondViewController *secondVC = [[SecondViewController alloc] init];
     [self presentViewController:secondVC animated:YES completion:nil];

     [secondVC setBlock:^(DataModel *dataModel){
         self.lblBlock.text = [NSString stringWithFormat:@"name:%@ address:%@",dataModel.name,dataModel.address];
     }];

     self.delegate = secondVC;
     if ([self.delegate respondsToSelector:@selector(passValueFromFirstVCToSecondVC:)]) {
         [self.delegate performSelector:@selector(passValueFromFirstVCToSecondVC:) withObject:self.firstDelegateModel];
     }
 }

 #pragma mark - 懒加载
 - (DataModel *)firstDelegateModel
 {
     if (!_firstDelegateModel) {
         _firstDelegateModel = [[DataModel alloc] init];
         _firstDelegateModel.name = @"GuYu";
         _firstDelegateModel.address = @"AnHui";
     }
     return _firstDelegateModel;
 }

 @end

 #import <UIKit/UIKit.h>
 #import "FirstViewController.h"
 @class DataModel;
 //定义block类型
 typedef void(^Block)(DataModel *dataModel);

 @interface SecondViewController : UIViewController <PassValueDelegate>
 //通知传值的传值者
 @property (nonatomic, strong) DataModel *secondNotificationModel;
 //代理传值的接受者
 @property (nonatomic, strong) DataModel *secondDelegateModel;
 //block的接受者
 @property (nonatomic, strong) Block block;

 @end

 #import "SecondViewController.h"
 #import "DataModel.h"

 @interface SecondViewController ()

 @property (strong, nonatomic) UILabel *label;

 @end

 @implementation SecondViewController
 - (void)viewDidLoad {
     [super viewDidLoad];
     [self.view setBackgroundColor:[UIColor groupTableViewBackgroundColor]];

     [self createButtonAndLabel];
 }
 #pragma mark - 创建标签和按钮
 - (void)createButtonAndLabel
 {
     //创建标签
     self.label = [[UILabel alloc] initWithFrame:CGRectMake(, , , )];
     [self.label setBackgroundColor:[UIColor redColor]];
     self.label.textAlignment = NSTextAlignmentCenter;
     [self.view addSubview:self.label];

     //创建按钮
     UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
     [btn setFrame:CGRectMake(, , , )];
     [btn setBackgroundColor:[UIColor blackColor]];
     [btn setTitle:@"goToBack" forState:UIControlStateNormal];
     [btn setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
     [btn addTarget:self action:@selector(goToBack) forControlEvents:UIControlEventTouchUpInside];
     [self.view addSubview:btn];

 }
 #pragma mark - block传值、通知传值
 //按钮关联方法
 - (void)goToBack
 {
     [self dismissViewControllerAnimated:YES completion:nil];

     //block传值
     self.block(self.secondNotificationModel);

     //通知传值
     [[NSNotificationCenter defaultCenter] postNotificationName:@"passValueFromSecondVCToFirstVC" object:self.secondNotificationModel];
 }

 #pragma mark - 代理协议方法
 - (void)passValueFromFirstVCToSecondVC:(DataModel *)dataModel
 {
     self.secondDelegateModel = dataModel;
     self.label.text = [NSString stringWithFormat:@"name:%@ address:%@",self.secondDelegateModel.name,self.secondDelegateModel.address];
 }

 #pragma mark - 懒加载
 //初始化_secondNotificationModel
 - (DataModel *)secondNotificationModel
 {
     if (!_secondNotificationModel) {
         _secondNotificationModel = [[DataModel alloc] init];
         _secondNotificationModel.name = @"Bowen";
         _secondNotificationModel.address = @"China";
     }
     return _secondNotificationModel;
 }
 //初始化self.block
 - (void)setBlock:(Block)block
 {
     _block = block;
 }

 @end