iOS链式编程思想学习(模仿masonry，写一个计算器)

masonry是现在项目中常用的自动布局第三方库，使用方法一般如下：

[otherDetectView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.and.right.equalTo(self.view);
        make.top.equalTo(lbaddItem.mas_bottom).offset(10);
        make.height.mas_equalTo(2*(buttonHeight+10)+10);
    }];

之所以有这种方便直观而又神奇的用法，是因为masonry的实现方法中包含了 链式编程思想，具体可以谷歌百度。

我模仿masonry写了一个计算器的demo，具体代码如下：

计算器管理器

//  计算器管理器（链式编程思想）

#import 

@class CaculatorMaker;
@interface NSObject (CalculatorManager)
//计算

+ (float)makCalulator:(void(^)(CaculatorMaker *make)) caaulatorMaker;

@end

#import "NSObject+CalculatorManager.h"
#import "CaculatorMaker.h"
@implementation NSObject (CalculatorManager)

+ (float)makCalulator:(void (^)(CaculatorMaker *))caaulatorMaker {
    CaculatorMaker *mgr = [CaculatorMaker new];
    caaulatorMaker(mgr);
    return mgr.result;
}
@end

CaculatorMaker

#import 

@interface CaculatorMaker : NSObject
@property (nonatomic,assign) float result;

//加法
- (CaculatorMaker *(^)(float))add;
//减
- (CaculatorMaker *(^)(float))sub;
//乘
- (CaculatorMaker *(^)(float))muilt;
//除
- (CaculatorMaker *(^)(float))divide;

@end

#import "CaculatorMaker.h"

@implementation CaculatorMaker

- (CaculatorMaker *(^)(float))add {
    return ^CaculatorMaker *(float value) {
        _result += value;
        return self;
    };
}

- (CaculatorMaker *(^)(float))sub {
    return ^CaculatorMaker *(float value) {
        _result -= value;
        return self;
    };
}
- (CaculatorMaker *(^)(float))muilt {
    return ^CaculatorMaker *(float value) {
        _result *= value;
        return self;
    };
}
- (CaculatorMaker *(^)(float))divide {
    return ^CaculatorMaker *(float value) {
        _result /= value;
        return self;
    };
}
@end

使用

float result = [NSObject makCalulator:^(CaculatorMaker *make) {
        make.add(1).add(5).sub(4).muilt(2).divide(3);
    }];