HTML部分
在网页上放置一个按钮和一个文本框，按钮用来向服务器发送信息，文本框用来显示从服务器传回的消息。
<!DOCTYPE html>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
<title></title>
<script type="text/javascript" src="js/loli.js"></script>
</head>
<body>
<p><input id="btn1" type="button" value="按钮" /></p>
<p><input id="txt1" type="text" /></p>
</body>
</html>WebSocket部分
window.onload = main;
var ws;
function main() {
var oBtn = document.getElementById('btn1');
oBtn.onclick = OnButton1;
}
function OnButton1() {
ws = new WebSocket('ws://localhost/ws');
ws.onopen = OnOpen;
ws.onmessage = OnMessage;
}
function OnOpen(event) {
ws.send('hello websocket');
}
function OnMessage(event) {
var oTxt = document.getElementById('txt1');
oTxt.value = event.data;
};后端部分
要想处理WebSocket请求，必须有一个
func (*websocket.Conn)类型的处理函数，例如：
func OnWebSocket(ws *websocket.Conn) {
defer ws.Close()
var err error
var str string
for {
if err = websocket.Message.Receive(ws, &str); err != nil {
break
} else {
fmt.Println("从客户端收到：", str)
}
str = "hello, I'm server."
if err = websocket.Message.Send(ws, str); err != nil {
break
} else {
fmt.Println("向客户端发送：", str)
}
}
}然后和一个网址对应起来：
http.Handle("/ws", websocket.Handler(OnWebSocket))完整代码如下：
package main
import (
"bytes"
"errors"
"fmt"
"html/template"
"net/http"
"runtime"
"golang.org/x/net/websocket"
)
// 端口
const (
HTTP_PORT string = "80"
HTTPS_PORT string = "443"
)
// 目录
const (
CSS_CLIENT_PATH = "/css/"
DART_CLIENT_PATH = "/js/"
IMAGE_CLIENT_PATH = "/image/"
CSS_SVR_PATH = "web"
DART_SVR_PATH = "web"
IMAGE_SVR_PATH = "web"
)
func init() {
runtime.GOMAXPROCS(runtime.NumCPU())
}
func main() {
// 先把css和脚本服务上去
http.Handle(CSS_CLIENT_PATH, http.FileServer(http.Dir(CSS_SVR_PATH)))
http.Handle(DART_CLIENT_PATH, http.FileServer(http.Dir(DART_SVR_PATH)))
// 网址与处理逻辑对应起来
http.HandleFunc("/", HomePage)
http.Handle("/ws", websocket.Handler(OnWebSocket))
// 开始服务
err := http.ListenAndServe(":"+HTTP_PORT, nil)
if err != nil {
fmt.Println("服务失败 /// ", err)
}
}
func WriteTemplateToHttpResponse(res http.ResponseWriter, t *template.Template) error {
if t == nil || res == nil {
return errors.New("WriteTemplateToHttpResponse: t must not be nil.")
}
var buf bytes.Buffer
err := t.Execute(&buf, nil)
if err != nil {
return err
}
res.Header().Set("Content-Type", "text/html; charset=utf-8")
_, err = res.Write(buf.Bytes())
return err
}
func HomePage(res http.ResponseWriter, req *http.Request) {
t, err := template.ParseFiles("web/loli.html")
if err != nil {
fmt.Println(err)
return
}
err = WriteTemplateToHttpResponse(res, t)
if err != nil {
fmt.Println(err)
return
}
}
func OnWebSocket(ws *websocket.Conn) {
defer ws.Close()
var err error
var str string
for {
if err = websocket.Message.Receive(ws, &str); err != nil {
break
} else {
fmt.Println("从客户端收到：", str)
}
str = "hello, I'm server."
if err = websocket.Message.Send(ws, str); err != nil {
break
} else {
fmt.Println("向客户端发送：", str)
}
}
}
