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(2021);

oDate.setFullYear(2022);
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());
writeDocument("打印今天是星期几-------------"); 
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()]);

writeDocument("打印2019年6月1日 星期六 15:59:59:999-------------"); 
var oPrintDate = new Date(2019, 5, 1, 15, 59, 59, 999);