Ios 将数据传递到根视图控制器

我有一个简单的应用程序，其结构如下：

• “A”：具有WebView的独立视图控制器
• “B”：导航控制器
• “C”：根视图控制器位于“B”中，是所有存储的表视图

当“A”中WebView的URL变得特定（）时，我需要：

按“C”

发送要在“C”中使用的字符串

我怎样才能做到这一点

Here you can do with delegate methods   

//这是调用委托方法的根ViewController

---

如果您遇到过这样的结构问题，可能需要在应用程序中正确实现模型层。。。

#import "ThirdViewController.h"
#import "SecondViewController.h"
 @interface ViewController ()<ThirdViewControllerDelegate>
  @end

@implementation ViewController
 #pragma mark -
 #pragma mark ThirdViewController Delegate Method

-(void)didSelectValue:(NSString *)value{
    NSLog(@"%@",value);
}

// Pass the last Vc delegate to the next ViewController

-(void)gotoSeconddVc{
    SecondViewController *vc2=[[SecondViewController alloc]init];
    vc2.lastDelegate=self;
    [self.navigationController pushViewController:vc2 animated:YES];
}


 #import "ThirdViewController.h"
     @interface SecondViewController : UIViewController
        @property(nonatomic,retain) id <ThirdViewControllerDelegate> lastDelegate;
        @end

-(void)gotoThirdVc{
    ThirdViewController *vc3=[[ThirdViewController alloc]init];
    vc3.delegate=self.lastDelegate;
    [self.navigationController pushViewController:vc3 animated:YES];
}

@implementation ThirdViewController


-(void)btnDoneClicked{
    [self.navigationController popToRootViewControllerAnimated:YES];
    [self.delegate didSelectValue:strValue]; //call delegate methods here
}