如何在HTTP请求上设置模块特定的自定义标头？(How can I set module specific custom headers on a HTTP request?)

 以下是在应用程序级别全局共享数据的最佳方法。 单身人士课程是一把钥匙。 Singleton仅初始化一次，其余时间返回共享数据。 
 
@interface Singleton : NSObject
@property (nonatomic, retain) NSMutableArray * globalArray;
  +(Singleton*)singleton;
@end

@implementation Singleton
@synthesize globalArray;
+(Singleton *)singleton {
    static dispatch_once_t pred;
    static Singleton *shared = nil;
    dispatch_once(&pred, ^{
        shared = [[Singleton alloc] init];
        shared.globalArray = [[NSMutableArray alloc]init];
    });
    return shared;
}
@end
 
 以下是访问/使用共享数据的方法。 
 
NSMutableArray * sharedData = [Singleton singleton].globalArray;

Following is best approach to share data Globally at Application level. Singleton Class is a key. Singleton is only initialised once, rest of times shared data is returned.
 
@interface Singleton : NSObject
@property (nonatomic, retain) NSMutableArray * globalArray;
  +(Singleton*)singleton;
@end

@implementation Singleton
@synthesize globalArray;
+(Singleton *)singleton {
    static dispatch_once_t pred;
    static Singleton *shared = nil;
    dispatch_once(&pred, ^{
        shared = [[Singleton alloc] init];
        shared.globalArray = [[NSMutableArray alloc]init];
    });
    return shared;
}
@end
 
Following is the way to access/use shared data.
 
NSMutableArray * sharedData = [Singleton singleton].globalArray;