Objective-c 实现单例设计模式

#import <Foundation/Foundation.h>

@interface Singleton : NSObject

@property (nonatomic,strong) NSString *singletonData;

+ (Singleton *)sharedManager;

@end

#import "Singleton.h"

@implementation Singleton

@synthesize singletonData =_singletonData;

static Singleton *sharedManager =nil;

+ (Singleton *)sharedManager

{

static dispatch_once_t once;

dispatch_once(&once, ^{

    sharedManager = [[selfalloc] init];

});

return sharedManager;

}

@end