writeToFile

- (void)loadData {
    // 结束与其相对的上拉数据刷新操作
    [self.tableView.footer endRefreshing];
    // 发送请求
    NSMutableDictionary *params = [NSMutableDictionary dictionary];
    params[@"a"] = @"list";
    params[@"c"] = @"data";
    params[@"type"] = @(self.type);
    _params = params;
    [[AFHTTPSessionManager manager] GET:@"http://api.budejie.com/api/api_open.php" parameters:params success:^(NSURLSessionDataTask *task, id responseObject) {
        if (_params != params) {
            return;
        }
        [responseObject writeToFile:@"/Users/liyang/Desktop/liyangtiezi.plist" atomically:YES
         ];
        // 字典 -> 模型
        _topics = [LYTopic objectArrayWithKeyValuesArray:responseObject[@"list"]];
        _maxtime = responseObject[@"info"][@"maxtime"];
        
        // 刷新表格
        [self.tableView reloadData];
        // 结束刷新
        [self.tableView.header endRefreshing];
        // 下拉刷新成功再清空页码为零
        page = 0;
    } failure:^(NSURLSessionDataTask *task, NSError *error) {
        if (_params != params) {
            return;
        }
        // 结束刷新
        [self.tableView.header endRefreshing];
    }];
}