當(dāng)網(wǎng)絡(luò)從離線變?yōu)樵诰€或者從在線變?yōu)殡x線時(shí)，分別觸發(fā)這兩個(gè)事件
window.addEventListener("online", function () {
//當(dāng)聯(lián)網(wǎng)的時(shí)候觸發(fā)的回調(diào)
}, false);
window.addEventListener("offline", function () {
//當(dāng)斷網(wǎng)的時(shí)候觸發(fā)的回調(diào)
}, false);
另外window.navigator.onLine可以檢測(cè)頁(yè)面首次加載的時(shí)候是否聯(lián)網(wǎng)，值為true或false
更加兼容的寫法
var EventUtil = {
addHandler: function(element, type, handler) {
if (element.addEventListener) {
element.addEventListener(type, handler, false);
} else if (element.attachEvent) {
element.attachEvent("on" + type, handler);
} else {
element["on" + type] = handler;
}
}
};
EventUtil.addHandler(window, "online", function() {
console.log("Online");
});
EventUtil.addHandler(window, "offline", function() {
console.log("Offline");
});
