5-GPS室外定位导航车的web mqtt完成通信

这里给出的方案是使用paho_mqtt.js 和mqttws31.js 实现。

html中调用标准库 api 接口实现 。通信使用

cJson 格式 键值对 。

例如

lonti:112.346233

lati:40.34555 

function MQTTconnect(){

            //  console.log(devid);
            client = new Paho.MQTT.Client(serverip, Number(port), "clientId1");
            client.onConnectionLost = onConnectionLost;//注册连接断开处理事件
            client.onMessageArrived = onMessageArrived;//注册消息接收处理事件
            client.connect({onSuccess:onConnect});//连接服务器并注册连接成功处理事件
            };
            function onConnect() {
              // Once a connection has been made, make a subscription and send a message.
              console.log("onConnect");

              client.subscribe(topic);
             // message = new Paho.MQTT.Message("Hello");
            //  message.destinationName = "/World";
            //  client.send(message); 
            };
            function onConnectionLost(responseObject) {
              if (responseObject.errorCode !== 0)
                console.log("onConnectionLost:"+responseObject.errorMessage);
                console.log("连接已断开");
            };     

            function onMessageArrived(message) {
            //console.log("收到消息:"+message.payloadString);
            //    console.log("主题："+message.destinationName);
            //  console.log("长度："+strlen(message.payloadString));
                if(strlen(message.payloadString)>30)
                {
                //  heading.update(headingI);//0~360 00
                   var temp1 = jQuery.parseJSON(message.payloadString);

                    //console.log("heading"+temp1.heading); 
                    console.log("解析出来的：humidity："+temp1.roll);
                    console.log("解析出来的：temperature："+temp1.pitch);

                    headingI =temp1.heading;
                    roll = temp1.roll;
                    pitch =temp1.pitch;
                    cpuload =temp1.cpuload;
                    cputemp = temp1.cputemp;
                    wifisignal =temp1.wifisignal;

                    $('#heading').val(headingI);
                    $('#wifistrength').val(wifisignal);
                    $('#cputem').val(cputemp);
                    $('#cpuload').val(cpuload);
                }