JS动态显示日期和时间

<span id="time"></span>

//显示当前时间日期，id表明在哪里显示
admin_index.showTime = function(id) {
    var today = new Date();
    var time = today.getFullYear() + "年" 
            + admin_index.timeFormat(today.getMonth() + 1) + "月" 
            + admin_index.timeFormat(today.getDate()) + "日 "
            + admin_index.getWeek() + " "
            + admin_index.timeFormat(today.getHours()) + ":" 
            + admin_index.timeFormat(today.getMinutes()) + ":" 
            + admin_index.timeFormat(today.getSeconds());
    $("#" + id).text(time);
};

admin_index.getWeek = function() {
    var day = new Date().getDay();
    if (day == "0") return "星期天";
    if (day == "1") return "星期一";
    if (day == "2") return "星期二";
    if (day == "3") return "星期三";
    if (day == "4") return "星期四";
    if (day == "5") return "星期五";
    if (day == "6") return "星期六";return "";
};

admin_index.timeFormat = function(value) {
    if (value >= 10) return value;
    return "0" + value;
};

//页面加载完成之后的操作
$(document).ready(function() {
    //显示时间
    setInterval(function(){admin_index.showTime("time");}, 1000);
});