说明：  1、首先是正常传输。在客户端，用户选择本地文件并将其发送到服务器端。在服务器端，客户端接收客户端发送的数据流，并根据IP地址将其存储在服务器端。 2。在文件传输过程中，针对客户端断开和服务器断开的情况，采取了不同的相应措施
(1.the first is the normal transmission. On the client side, the user selects a local file and sends it to the server side. On the server side, the client receives the data stream transmitted by the client and stores it on the server side according to the IP address. 2. In the process of file transmission, different corresponding measures are made for the case of client disconnection and server disconnection.)