我们一般会写很多的分类，这样会极大的方便的我们的代码。
比如我们需要给创建的一个UILabel对象赋值一些属性，常规的写法一般如下：

 _priceLb.font =  kFontPingFangRegularSize(10.f);
 _priceLb.textColor = kColor_666666;

但是我们如果使用链式语法实现其功能，并用分类添加新的属性，重写其get方法，我们的代码可以是这样的：

 weakSelf.hsSearchLb.aFont(kFontPingFangBoldSize(16)).
            aTextColor([UIColor blackColor]);

 _hsSearchLb.aFont(kFontPingFangBoldSize(16)).
        aTextColor([UIColor blackColor]).
        aAlignment(NSTextAlignmentCenter).
        aText(@"花生搜索");

具体实现代码

#import <UIKit/UIKit.h>

typedef UILabel *(^LeeFontBlock)(UIFont *aFontSize);
typedef UILabel *(^LeeTextBlock)(NSString *aText);
typedef UILabel *(^LeeTextColorBlock)(UIColor *aColor);
typedef UILabel *(^LeeNumberOfLinesBlock)(NSInteger aNumber);
typedef UILabel *(^LeeTextAlignmentBlock)(NSTextAlignment aAlignment);

@interface UILabel (LeeChainBlock)

@property (nonatomic,copy,readonly) LeeFontBlock aFont;
@property (nonatomic,copy,readonly) LeeTextColorBlock aTextColor;
@property (nonatomic,copy,readonly) LeeTextBlock aText;
@property (nonatomic,copy,readonly) LeeNumberOfLinesBlock aNumberOfLines;
@property (nonatomic,copy,readonly) LeeTextAlignmentBlock aAlignment;

@end

#import "UILabel+LeeChainBlock.h"

@implementation UILabel (LeeChainBlock)

- (LeeTextBlock)aText{
    __weak typeof(self) weakSelf = self;
    return ^(NSString *aTextStr){
        __strong typeof(weakSelf) strongSelf = weakSelf;
        strongSelf.text = aTextStr;
        return strongSelf;
    };
}

- (LeeNumberOfLinesBlock)aNumberOfLines{
    __weak typeof(self) weakSelf = self;
    return ^(NSInteger aNumber){
        __strong typeof(weakSelf) strongSelf = weakSelf;
        strongSelf.numberOfLines = aNumber;
        return strongSelf;
    };
}

- (LeeFontBlock)aFont{
    __weak typeof(self) weakSelf = self;
    return ^(UIFont *aFont){
        __strong typeof(weakSelf) strongSelf = weakSelf;
        strongSelf.font = aFont;
        return strongSelf;
    };
}

- (LeeTextColorBlock)aTextColor{
    __weak typeof(self) weakSelf = self;
    return ^(UIColor *aColor){
        __strong typeof(weakSelf) strongSelf = weakSelf;
        strongSelf.textColor = aColor;
        return strongSelf;
    };
}

- (LeeTextAlignmentBlock)aAlignment{
    __weak typeof(self) weakSelf = self;
    return ^(NSTextAlignment aAlignment){
        __strong typeof(weakSelf) strongSelf = weakSelf;
        strongSelf.textAlignment = aAlignment;
        return strongSelf;
    };
}



@end

如下是链式语法相关博客
第一篇：链式语法实现分析
第二篇：链式语法使用实战