使用jQuery頁面加載函數啟動定時任務

var timer;
$(document).ready(function(){
    if (timer == undefined)
        timer = window.setInterval(showTime, 1000);
});

 

//顯示時間
function showTime() {
    var now = new Date();
    document.getElementById("spanTime").innerHTML = now.toLocaleTimeString();
}