本文实例讲述了Javascript实现网络监测的方法。分享给大家供大家参考。具体实现方法如下：

该代码可监测网络是否连接及网速的快慢状态。

(function(){

var network = function(){

var monitor = this;

/**

* @param {Funcation} speedInterval

*/

var speedInterval = null;

/**

* @param {Function} networkInterval

*/

var networkInterval = null;

/**

* @param {Function} reNetworkInterval

*/

var reNetworkInterval = null;

var time = 5000;

/**

* 获取网络连接状态

*/

var getConnectState = function(){

return navigator.onLine ? 1 : 0;

};

/**

* 网络中断

*/

var disconnect = function(){

// TODO ...

console.log("网速中断");

window.clearInterval(reNetworkInterval);

reNetworkInterval = null;

endSpeed();

endNetwork();

window.setTimeout(function(){

reNetworkInterval = window.setInterval(function(){

if (getConnectState() == 1) {

window.clearInterval(reNetworkInterval);

reNetworkInterval = null;

startSpeed();

startNetwork();

} else {

window.clearInterval(reNetworkInterval);

reNetworkInterval = null;

disconnect();

}

}, time);

}, 2 * time);

};

/**

* 网络速度

*/

var speed = {

/**

* 网速过慢

*/

bad : function(){

// TODO ...

console.log("网速过慢");

window.setTimeout(function(){

if(getConnectState() == 1) {

window.clearInterval(networkInterval);

networkInterval = null;

startSpeed();

} else {

disconnect();

}

}, 2 * time);

},

/**

* 网速中等

*/

medium : function(){

// TODO ...

console.log("网速中等");

},

/**

* 网速极佳

*/

great : function(){

// TODO ...

console.log("网速极佳");

}

};

/**

* 开启速度监测

* @private

*/

var startSpeed = function(){

window.clearInterval(speedInterval);

speedInterval = null;

if(getConnectState() == 1) {

speedInterval = window.setInterval(function(){

var start = new Date().getTime();

if (getConnectState() == 1) {

var img = document.getElementById("networkSpeedImage");

if (!!!img) {

img = document.createElement("IMG");

img.id = "networkSpeedImage";

img.style.display = "none";

document.body.appendChild(img);

}

try {

img.src = "http://www.baidu.com/img/baidu_jgylogo3.gif?_t=" + new Date().getTime();

img.onload = function(){

var end = new Date().getTime();

var delta = end - start;

if (delta > 200) {

speed.bad();

} else if (delta > 100) {

speed.medium();

} else {

speed.great();

}

};

} catch(e){

speed.bad();

}

} else {

// TODO 网络断开

disconnect();

}

}, time);

}else {

// TODO 网络断开

disconnect();

}

};

/**

* 停止速度监测

* @private

*/

var endSpeed = function(){

window.clearInterval(speedInterval);

speedInterval = null;

};

/**

* 开启网络连接监测

* @private

*/

var startNetwork = function(){

if (getConnectState() == 1) {

networkInterval = window.setInterval(function(){

if (getConnectState() == 0) {

disconnect();

}

}, time);

} else{

disconnect();

}

};

/**

* 结束网络连接监测

* @private

*/

var endNetwork = function(){

window.clearInterval(networkInterval);

networkInterval = null;

};

/**

* 网络监控开始

*/

this.start = function(){

startNetwork();

startSpeed();

};

/**

* 停止网络监控

*/

this.stop = function(){

endSpeed();

endNetwork();

};

};

window.network = new network();

}).call(this);

// 调用的时候,直接调用network.start();

希望本文所述对大家的javascript程序设计有所帮助。