iOS学习小结（一）

1.给类目添加属性需要使用runtime关联

#import <Foundation/Foundation.h>

@interface NSURLRequest (AIFNetworkingMethods)

@property (nonatomic, copy) NSDictionary *requestParams;
@end 

#import "NSURLRequest+AIFNetworkingMethods.h"
#import <objc/runtime.h>

static void *AIFNetworkingRequestParams;

@implementation NSURLRequest (AIFNetworkingMethods)

- (void)setRequestParams:(NSDictionary *)requestParams
{
    objc_setAssociatedObject(self, &AIFNetworkingRequestParams, requestParams, OBJC_ASSOCIATION_COPY);
}

- (NSDictionary *)requestParams
{
    return objc_getAssociatedObject(self, &AIFNetworkingRequestParams);
}
@end