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;
}