server.address()

• 返回：<Object> | <string> | <null>

返回绑定的 address、地址 family 名称和服务器的 port，如果监听的是 IP 套接字，则由操作系统报告（在获取操作系统分配的地址时，用于查找分配的端口）：{ port: 12346, family: 'IPv4', address: '127.0.0.1' }。

【Returns the bound address, the address family name, and port of the server as reported by the operating system if listening on an IP socket (useful to find which port was assigned when getting an OS-assigned address): { port: 12346, family: 'IPv4', address: '127.0.0.1' }.】

对于监听管道或 Unix 域套接字的服务器，名称将以字符串形式返回。

【For a server listening on a pipe or Unix domain socket, the name is returned as a string.】

const server = net.createServer((socket) => {
  socket.end('goodbye\n');
}).on('error', (err) => {
  // Handle errors here.
  throw err;
});

// Grab an arbitrary unused port.
server.listen(() => {
  console.log('opened server on', server.address());
}); 拷贝

server.address() 在 'listening' 事件触发之前或调用 server.close() 之后会返回 null。