大话设计模式之简单的工厂模式

第一章：代码无错就是优-简单的工厂模式

先建立一个计算类Operation

Operation.h文件

@interface Operation : NSObject

@property(nonatomic,assign)double numberA;

@property(nonatomic,assign)double numberB;

@end

 Operation.m文件

@implementation Operation

 

@end

 然后分别创建他们的子类Add,Sub,Mul,Div

Add.h

#import "Operation.h"

 

@interface Add : Operation

-(double)OperationAdd;

@end

Add.m

#import "Add.h"

 

@implementation Add

-(double)OperationAdd{

    return self.numberA+self.numberB;

}
@end

Sub.h

#import "Operation.h"

@interface Sub : Operation
-(double)operaSub;
@end

Sub.m

#import "Sub.h"

@implementation Sub
- (double)operaSub{
      return self.numberA-self.numberB;
}
@end

Mul.h

#import "Operation.h"

@interface Mul : Operation
-(double)OperaMul;
@end

Mul.m

#import "Mul.h"

@implementation Mul
-(double)OperaMul{
    return self.numberA*self.numberB;
}
@end

Div.h

#import "Operation.h"

@interface Div : Operation
-(double)OperaDiv;
@end

Div.m

#import "Div.h"

@implementation Div
-(double)OperaDiv{
//    double result=0.0;
    if (self.numberB==0) {
           NSLog(@"除数不能为0");
       }
           return self.numberA/self.numberB;
}
@end

计算的工厂类OperationFactory.h

#import <Foundation/Foundation.h>

#import "Add.h"

#import "Sub.h"

#import "Mul.h"

#import "Div.h"

@interface OperationFactory : NSObject

-(Operation *)createOperate:(char)opreate;

@end

OperationFactory.m

#import "OperationFactory.h"

@implementation OperationFactory
-(Operation *)createOperate:(char)opreate{
    Operation *oper;
    switch (opreate) {
        case '+':
            oper=[[Add alloc]init];
            break;
        case '-':
            oper=[[Sub alloc]init];
         
            break;
            
        case '*':
            oper=[[Mul alloc]init];
          
               break;
            
        case '/':
            oper=[[Div alloc]init];
         
            break;
    }
    return oper;
}
@end

主函数

#import <Foundation/Foundation.h>
#import "OperationFactory.h"
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        OperationFactory *factory=[[OperationFactory alloc]init];
        Operation *oper=[factory createOperate:'+'];
        oper.numberA=100;
        oper.numberB=200;
        NSLog(@"%f",[oper opera]);
    }
        return 0;
}