行为型之一-职责链模式

Chain of Responsibility（职责链模式）

使多个对象都有机会处理请求，从而避免请求的发送者和接收者之间的耦合关系。将这个对象连成一条链，并沿着这条链传递该请求，直到有一个对象处理它为止。

iOS事件的传递和响应就是职责链模式的实现。

VC.m

HCDCommonManager *common = [[HCDCommonManager alloc]initWithName:@"经理"];
HCDMajorManager *majon = [[HCDMajorManager alloc]initWithName:@"总监"];
HCDGenaralManager *genaral = [[HCDGenaralManager alloc]initWithName:@"总经理"];
common.superior = majon;
majon.superior = genaral;

HCDReuquest *request = [[HCDReuquest alloc]init];
request.requestType = @"请假";
request.number = 5;
[common dealRequest:request];

request.number = 20;
[common dealRequest:request];

request.number = 220;
[common dealRequest:request];

request.number = 1200;
[common dealRequest:request];

HCDMnager.h

@interface HCDMnager : NSObject
@property(nonatomic,copy)NSString *name;
@property(nonatomic,strong)HCDMnager *superior;
-(instancetype)initWithName:(NSString *)name;
-(void)dealRequest:(HCDReuquest *)request;
@end

HCDMnager.m

@implementation HCDMnager
-(instancetype)initWithName:(NSString *)name{
    self = [super init];
    if (self) {
        _name = name;
    }
    return self;
}
-(void)dealRequest:(HCDReuquest *)request{
    
}
@end

HCDCommonManager.m

@implementation HCDCommonManager
-(void)dealRequest:(HCDReuquest *)request{
    if ([request.requestType isEqualToString:@"请假"] && request.number < 10) {
        NSLog(@"%@处理了%@,时间是%ld",self.name,request.requestType,request.number);
    }else{
        [self.superior dealRequest:request];
    }
}
@end

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