iOS应用设计模式开发中对简单工厂和工厂方法模式的运用

复制代码
#import "OperationFactory.h"

 

+(Operation*)CreateOperate:(char)operate{
    Operation *oper;
    switch(operate) {
        case '+':
            oper = [[OperationAdd alloc]init];
            break;
        case '-':
            oper = [[OperationSub alloc]init];
            break;
        case '*':
            oper = [[OperationMul alloc]init];
            break;
        case '/':
            oper = [[OperationDiv alloc]init];
            break;
        default:
            oper = nil;
            break;
        }
        return oper;
}

具体调用
复制代码
#import <Foundation/Foundation.h>
#import "OperationAdd.h"
#import "OperationDiv.h"
#import "OperationMul.h"
#import "OperationSub.h"
#import "OperationFactory.h"

 

int main (int argc,const char* argv[])
{
    @autoreleasepool{
        Operation *oper = [OperationFactory CreateOperate:'*'];
        [oper setNumberA:1];
        [oper setNumberB:2];
        double result = 0;
        result = [oper GetResult];
        NSLog(@"Result is %f", result);
    }
    return 0;
}

好啦，上面罗列的是简单工厂模式的基础代码。其实还是挺简单的，对吧，只有一层继承关系，一个依赖关系，在工厂类里面用switch语句判别需要实例化哪种类型，之后进行计算，获取结果。