实现客户端和服务器端通信，客户端登录用户名admin密码12345，登录成功后发送命令，服务器端返回命令执行情况：正确则执行，错误则返回出错信息。-The achievement of client and server communication, client login username admin password 12345, send a command after a successful login, the server-side implementation of the r