#项目中需要给系统类添加属性

#需要注意的地方就是.m中   set 和 get  ，get方法中方法名和添加的属性名一致，set中可以用驼峰

 

#import 
     
      @interface UITextField (AddProperty)/** 添加额外标签*/@property (nonatomic, copy)  NSString* otherTag;@end
     

////  UITextField+AddProperty.m//  phone-wisdomFarmland////  Created by apple on 2019/2/19.//  Copyright © 2019年 apple. All rights reserved.//#import "UITextField+AddProperty.h"#import 
     
      static NSString *targetVaulekey = @"test_otherTagKey";@implementation UITextField (AddProperty)@dynamic otherTag;-(NSString *)otherTag{    return objc_getAssociatedObject(self, &targetVaulekey);}- (void)setOtherTag:(NSString *)otherTag{    objc_setAssociatedObject(self, &targetVaulekey, otherTag, OBJC_ASSOCIATION_RETAIN);}@end