
建议用如下方式导入头文件:
#if __has_include(<AFNetworking/AFNetworking.h>)
#import <AFNetworking/AFNetworking.h>
#elif __has_include("AFNetworking.h")
#import "AFNetworking.h"
#elif __has_include("AFNetworking-umbrella.h")
#import "AFNetworking-umbrella.h"
#else
#error "AFNetworking header not found"
#endif