最近有朋友問(wèn)通知的底層怎么實(shí)現(xiàn)，然后我大致的理了下:
1.通知是單例來(lái)的
2.通知可以注冊(cè)與注銷，說(shuō)明里面有數(shù)組在控制著
3.通知是要實(shí)現(xiàn)方法的，說(shuō)明里面有協(xié)議存在
4.通知是有設(shè)置通知接收者的，說(shuō)明這是使用了代理的

綜合上述說(shuō)明，我自己基于blcok寫(xiě)了套自己的通知：
主要是使用兩個(gè)方法

// 接收通知
+ (void)addBlocksObject:(NotifBlock)object WithKey:(NSString *)key;

// 發(fā)送通知
+ (void)sendNotificationWithKey:(NSString *)key Info:(NSDictionary *)message;

先在需要接收的地方添加上block，然后在需要傳值出來(lái)的地方發(fā)送通知（信息通過(guò)message來(lái)傳遞）

使用方法
先對(duì)應(yīng)key添加blcok

 [NotificationCenterBlock addBlocksObject:^(NSDictionary *info) {
        NSLog(@"%s -- %@",__func__,info);
    } WithKey:@"zzz"];

然后再對(duì)應(yīng)key發(fā)送消息

 [NotificationCenterBlock sendNotificationWithKey:@"zzz" Info:@{@"JAJAAA":@"SSDDDDD",@"JAJAAAss":@"SSDDDDDss"}];

其中的key就是接收和發(fā)送的識(shí)別鑰匙，也就是對(duì)應(yīng)key發(fā)送與添加block，同時(shí)這里的block是可以添加多個(gè)的。

下面是這個(gè)通知類的代碼

NotificationCenterBlock.h

//
//  NotificationCenterBlock.h
//  ZZZ
//
//  Created by zxw on 17/5/4.
//  Copyright ? 2017年 tianshikechuang. All rights reserved.
//

#import <Foundation/Foundation.h>

typedef void(^NotifBlock)(NSDictionary * info);

@interface NotificationCenterBlock : NSObject

// 發(fā)送通知
+ (void)sendNotificationWithKey:(NSString *)key Info:(NSDictionary *)message;

// 接收通知
+ (void)addBlocksObject:(NotifBlock)object WithKey:(NSString *)key;



+ (instancetype)shareNotificationCenterBlockWithKey:(NSString *)key;
+ (instancetype)NotificationCenterBlockWithKey:(NSString *)key;
- (instancetype)initNotificationCenterBlockWithKey:(NSString *)key;

- (void)sendNotificationInfo:(NSDictionary *)message;

- (void)addBlocksObject:(NotifBlock)object;
- (void)removeAllBlocksObject;


+ (void)removeAllBlocksObjectWithKey:(NSString *)key;

@end

NotificationCenterBlock.m

//
//  NotificationCenterBlock.m
//  ZZZ
//
//  Created by zxw on 17/5/4.
//  Copyright ? 2017年 tianshikechuang. All rights reserved.
//

#import "NotificationCenterBlock.h"


@interface NotificationCenterBlock ()

@property(nonatomic, strong) NSString * key;
@property(nonatomic, strong) NSMutableDictionary * keyBlockDic;

@end



@implementation NotificationCenterBlock

/* --- 單例創(chuàng)建 --- */
static NotificationCenterBlock *notif = nil;
- (instancetype)init{
    
    if (notif) {
        return notif;
    }
    
    if (self = [super init]) {
        self.keyBlockDic = [NSMutableDictionary dictionary];
        notif = self;
    }
    return self;
}


- (instancetype)initNotificationCenterBlockWithKey:(NSString *)key{
    self = [[NotificationCenterBlock alloc] init];
    self.key = key;
    return self;
}

+ (instancetype)shareNotificationCenterBlockWithKey:(NSString *)key{
    return [NotificationCenterBlock NotificationCenterBlockWithKey:key];
}

+ (instancetype)NotificationCenterBlockWithKey:(NSString *)key{
    return [[NotificationCenterBlock alloc] initNotificationCenterBlockWithKey:key];
}




/* --- 發(fā)送通知 --- */
+ (void)sendNotificationWithKey:(NSString *)key Info:(NSDictionary *)message{
    
    NotificationCenterBlock * notif = [NotificationCenterBlock shareNotificationCenterBlockWithKey:key];
    [notif sendNotificationInfo:message];

}

- (void)sendNotificationInfo:(NSDictionary *)message{
    NSMutableArray * arr = [self.keyBlockDic valueForKey:self.key];
    if (!arr) {
        return;
    }
    for (NotifBlock blcok in arr) {
        blcok(message);
    }
    
    self.keyBlockDic[self.key] = arr;
}





/* --- 添加和移除 --- */
+ (void)addBlocksObject:(NotifBlock)object WithKey:(NSString *)key{
     NotificationCenterBlock * notif = [NotificationCenterBlock shareNotificationCenterBlockWithKey:key];
    [notif addBlocksObject:object];
}
+ (void)removeAllBlocksObjectWithKey:(NSString *)key{
    NotificationCenterBlock * notif = [NotificationCenterBlock shareNotificationCenterBlockWithKey:key];
    [notif removeAllBlocksObject];
}


- (void)addBlocksObject:(__autoreleasing NotifBlock)object{
    
    if (!object) return;
    
    NSMutableArray * arr = [self.keyBlockDic valueForKey:self.key];
    if (!arr) {
        arr = [NSMutableArray array];
    }
    [arr addObject:object];
    
    self.keyBlockDic[self.key] = arr;
    
}

- (void)removeAllBlocksObject{
    
    NSMutableArray * arr = [self.keyBlockDic valueForKey:self.key];
    if (arr) {
        [arr removeAllObjects];
    }
    
    self.keyBlockDic[self.key] = arr;
}


@end

如果有什么地方有漏洞希望大家及時(shí)指出，以便及時(shí)更改！