today = new Date();

if (today.getYear() <2000)
{
document.write(today.getYear()+1900);
}
else
{
document.write(today.getYear());
}
document.write(' 年 ');
document.write(today.getMonth()+1);
document.write(' 月 ');
document.write(today.getDate());
document.write(' 日　　');

if (today.getDay()==0)
{
 document.write('星 期 日');
}
else if (today.getDay()==1)
{
 document.write('星 期 一');
}
else if (today.getDay()==2)
{
 document.write('星 期 二');
}
else if (today.getDay()==3)
{
 document.write('星 期 三');
}
else if (today.getDay()==4)
{
 document.write('星 期  四');
}
else if (today.getDay()==5)
{
 document.write('星 期 五');
}
else if (today.getDay()==6)
{
 document.write('星 期 六');
}