WebSocket是html5新增加的特性之一，可以实现客户端和服务器彼此之间相互通信，也可以实现跨域通信，目前大部分主流浏览器都支持，iE浏览器需要10版本以上。
需求：公司项目有一个报警模块，当后台接收到报警消息之后，需要及时的推送到浏览器上，显示给用户。
效果图如下：
参考代码如下：
jsp代码：
<%@ page contentType="text/html;charset=UTF-8" language="java"%> <div class="page-header navbar navbar-fixed-top"> <div class="page-header-inner"> <div class="page-logo"> <a href="<c:url value="/"/>"><img src="<c:url value="/img/logo.png"/>" style="height: 14px" alt="logo" class="logo-default" /></a> <div class="menu-toggler sidebar-toggler hide"></div> </div> <a href="javascript:;" class="menu-toggler responsive-toggler" data-toggle="collapse" data-target=".navbar-collapse"></a> <div class="top-menu"> <ul class="nav navbar-nav pull-right"> <li class="dropdown dropdown-alert"><a href="#" class="dropdown-toggle" data-toggle="dropdown" data-hover="dropdown" data-close-others="true"> <span class="badge pull-left"></span><label class="hidden-sm">报警</label><i class="fa fa-bell"></i> </a> <ul class="dropdown-menu"> </ul></li> <li class="dropdown dropdown-user"><a href="#" class="dropdown-toggle" data-toggle="dropdown" data-hover="dropdown" data-close-others="true"> <span class="username username-hide-on-mobile">你好，${sessionScope.username}</span> <i class="fa fa-angle-down"></i> </a> <ul class="dropdown-menu"> <li><a href="javascript:;" id="updatePass"><i class="icon-lock"></i>修改密码</a></li> <li><a href="<c:url value="/logout"/> "><i class="icon-key"></i>退出登录</a></li> </ul></li> </ul> </div> </div> </div> <div class="clearfix"></div> <script> //toastr.sos(num1) </script> <script type="text/javascript" src="http://cdn.bootcss.com/jquery/3.1.0/jquery.min.js"></script> <script type="text/javascript" src="http://cdn.bootcss.com/sockjs-client/1.1.1/sockjs.js"></script> <script type="text/javascript"> function wsPath() { var pathName = window.document.location.pathname; var host = window.location.host; var projectName = pathName.substring(0, pathName.substr(1).indexOf('/') + 1); return (host + projectName); } wsPath = wsPath(); var websocket = null; if ('WebSocket' in window) { websocket = new WebSocket("ws://" + wsPath + "/websocket/socketServer"); } else if ('MozWebSocket' in window) { websocket = new MozWebSocket("ws://" + wsPath + "/bison/websocket/socketServer"); } else { websocket = new SockJS("http://" + wsPath + "/bison/sockjs/socketServer"); } websocket.onmessage = onMessage; websocket.onope = onOpen; websocket.onerror = onError; websocket.onclose = onClose; function onOpen() { } function onMessage(evt) { var $uncheckedAlertMenuBtn = $("a.dropdown-toggle", $uncheckedAlertMenu); var $uncheckedAlertBadge = $("span.badge", $uncheckedAlertMenuBtn); var $uncheckedAlertMenu = $('li.dropdown-alert'); var $uncheckedAlertList = $('ul', $uncheckedAlertMenu); var a = $uncheckedAlertBadge.html(); $uncheckedAlertBadge.html(Number(a) + 1); //判断报警类型 如果是位置偏移，place+1 if (evt.data == "1") { var count; var a = $("#number").html(); if (a == null) { count = 1; $uncheckedAlertList .prepend('<li class="place-alert"><a href="alert?menuId=274"> <font color="red" id="place-alert">' + "位置报警(<font id ='number'>" + count + "</font>)" + '</font></a></li>'); } else { count = Number(a) + 1; $("#place-alert").html( "位置偏移(<font id='number'>" + count + "</font>)"); } } if (evt.data == "0") { var count; var a = $("#snum").html(); if (a == null) { count = 1; $uncheckedAlertList .prepend('<li class="sos-alert"> <a href="alert?menuId=274"><font color="red" id="sos-alert">' + "SOS报警(<font id='snum'>" + count + ")</font>" + '</font></a></li>'); } else { count = Number(a) + 1; $("#sos-alert").html( "SOS报警(<font id='snum'>" + count + "</font>)"); } } } function onError() { websocket.close(); } function onClose() { } window.close = function() { websocket.onclose(); } </script>
