AFNetworking 添加请求头

  AFNetworking请求，在请求头里添加令牌token，一般在请求的参数里已经带token过来了，可以先做一个筛选，有token的放请求头里，没有的不作处理正常请求就好，上代码

 AFHTTPSessionManager * manager = [AFHTTPSessionManager shareInstance];        NSMutableDictionary * dict = [[NSMutableDictionary alloc]initWithDictionary:parameters];    if ([dict.allKeys containsObject:@"token"]) {        [manager.requestSerializer setValue:@"your token" forHTTPHeaderField:@"token"];        //请求参数里token的键值对去掉        [dict removeObjectForKey:@"token"];    }        else        [manager.requestSerializer setValue:@"application/x-www-form-urlencoded; charset=utf-8" forHTTPHeaderField:@"Content-Type"];        manager.responseSerializer = [AFJSONResponseSerializer serializerWithReadingOptions:NSJSONReadingAllowFragments];    [manager POST:url parameters:dict progress:^(NSProgress * _Nonnull uploadProgress) {            } success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject) {            } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {            }];