SOURCE

function writeDocument(variable) {
    document.write(variable + "<br/>");
} 

writeDocument("定义时间对象--------------");
var oToday = new Date();

writeDocument("获取年月日时分秒毫秒--------------");
writeDocument("年：" + oToday.getFullYear());
writeDocument("月：" + oToday.getMonth());
writeDocument("日：" + oToday.getDate());
writeDocument("时：" + oToday.getHours());
writeDocument("分：" + oToday.getMinutes());
writeDocument("秒：" + oToday.getSeconds());
writeDocument("毫秒：" + oToday.getMilliseconds());

writeDocument("设置年月日时分秒毫秒--------------");
var oDate = new Date(2019);

oDate.setFullYear(2020);
writeDocument("年：" + oDate.getFullYear());
oDate.setMonth(5);
writeDocument("月：" + (oDate.getMonth() + 1));
oDate.setDate(1);
writeDocument("日：" + oDate.getDate());
oDate.setHours(16);
writeDocument("时：" + oDate.getHours());
oDate.setMinutes(58);
writeDocument("分：" + oDate.getMinutes());
oDate.setSeconds(59);
writeDocument("秒：" + oDate.getSeconds());
oDate.setMilliseconds(999);
writeDocument("毫秒：" + oDate.getMilliseconds());

var weeks = ["星期日","星期一","星期二","星期三","星期四","星期五","星期六",];

writeDocument("今天是" + weeks[oToday.getDay()]);

var oPrintDate = new Date(2019,5,1,15,59,59,999);

writeDocument("打印2019年6月1日 星期六 15:59:59:999--------");
oDate.setFullYear(2019);
writeDocument(oPrintDate.getFullYear());
oDate.setMonth(5);
writeDocument((oPrintDate.getMonth() + 1));
oDate.setDate(1);
writeDocument(oPrintDate.getDate());
oDate.setHours(15);
writeDocument(oPrintDate.getHours());
oDate.setMinutes(59);
writeDocument(oPrintDate.getMinutes());
oDate.setSeconds(59);
writeDocument(oPrintDate.getSeconds());
oDate.setMilliseconds(999);
writeDocument(oPrintDate.getMilliseconds());

writeDocument(oPrintDate.getFullYear()+"年"+(oPrintDate.getMonth() + 1)+"月"+oPrintDate.getDate()+"日"+ weeks[oPrintDate.getDay()] + oPrintDate.getHours() + ":"+ oPrintDate.getMinutes() + ":" + oPrintDate.getSeconds() +":"+ oPrintDate.getMilliseconds());