Golang a simple chat program based on TCP/IP

This is a creation in Article, where the information may have evolved or changed.

Server.go

Package Mainimport ("FMT" "IO" "NET" "OS" "strings") func main () {addr, err: = Net. RESOLVETCPADDR ("TCP", ": 4040") Checkerr (Err) Listen, err: = Net. LISTENTCP ("tcp", addr) Checkerr (err) fmt. PRINTLN ("Start server ...") for {conn, err: = Listen. Accept () Checkerr (err) go Handle (conn)//each time a connection is established, it is processed in a separate thread}}const buflength = 128var users map[string]net. Conn = Make (map[string]net. Conn, func Handle (Conn net). Conn) {Conn. Write ([]byte ("Welcome to 2B Chat Group ~")) for {data: = make ([]byte, 0)//here do an input buffer to avoid data being too long to read to incomplete data buf: = Make ([]byte, buflength) for {n, ERR: = conn. Read (BUF) if err! = Nil && Err! = Io. EOF {checkerr (err)}data = append (data, buf[:n] ...) if n! = buflength {break}}cmd: = strings. Split (String (data), "|") Fmt. Println ("command:", cmd) switch cmd[0] {case "Nick": FMT. PRINTLN ("Registered name:" + cmd[1]) users[cmd[1]] = conncase "Say": For K, V: = Range users {if k! = cmd[1] {fmt. Println ("give" + K + "Send message:" + cmd[2]) v.write ([]byte (cmd[1] + ": [" + cmd[2] + "]"))}}}}}func Checkerr (err error) {if Err! = N Il {fmt. PRINTLN (ERR) OS. Exit(-1)}} 

Client.go

package mainimport ("fmt""io""net""os")var nick string = ""func main() {addr, err := net.ResolveTCPAddr("tcp", ":4040")checkErr(err)conn, err := net.DialTCP("tcp", nil, addr)checkErr(err)// 读取提示data := make([]byte, 1024)conn.Read(data)fmt.Println(string(data))// 输入昵称fmt.Print("输入昵称:")fmt.Scanf("%v", &nick)fmt.Println("Hello " + nick)conn.Write([]byte("nick|" + nick))go Handle(conn)for {someTex := ""fmt.Scanf("%v", &someTex)conn.Write([]byte("say|" + nick + "|" + someTex))}}const BufLength = 128func Handle(conn net.Conn) {for {data := make([]byte, 1024)buf := make([]byte, BufLength)for {n, err := conn.Read(buf)if err != nil && err != io.EOF {checkErr(err)}data = append(data, buf[:n]...)if n != BufLength {break}}fmt.Println(string(data))}}func checkErr(err error) {if err != nil {fmt.Println(err)os.Exit(-1)}}