translate timestamp date of birth - in the name of the day

i'm trying to开发者_运维问答 translate a birth date in the "name" of the day, like monday, tuesday, etc. but i have some doubts on how to do it, i thought first : take the two timestamps (date of birth and current timestamp) and then use a "modulo" like %7 , then with the "rest" of the modulo looking through an array of names. But, actually, the timestamp is not meant to be divided by a modulo isn't it? how would you do?

Thanks

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You can get the UNIX Timestamp using valueOf() function where you can use modulo but you might try using easier API to get the day name from a date. I have taken the actual date of birth, say 14 April 1983 in a timestamp format. I get the monthly date value and month value form the actual DOB. I construct another date object with the monthly-date and month value and current year's value. Then I get the weekly day value (0-6 = Sun-Sat) from this date, and show the mapped day name from the array containing the names of the days.

var days = "Sunday,Monday,Tuesday,Wednesday,Thursday,Friday,Saturday";
var actualDOB = "04/14/1983";

var date = new Date(new Date().getFullYear(), new Date(actualDOB).getMonth(), new Date(actualDOB).getDate());

alert("The day of the week this year for your birthday is : " + days.split(',')[date.getDay()] + " (" + date.toDateString() + ")");

Hope this helps.

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If you have a real Date object, you can use the getDay() method of it in combination with an array of weekdays. Same goes for months. Here's a function to return the formatted actual birthday, the original day of birth and the day for the birthday this year:

function birthDAY(dat){
  var result = {},
      birthday = new Date(dat),
      weekdays = 'sun,mon,tue,wedness,thurs,fri,satur'.split(','),
      months = 'jan,feb,mar,apr,may,jun,jul,aug,sep,oct,nov,dec'.split(','),
      dateFormatted = function(dateobj) {
         return [
                 weekdays[dateobj.getDay()],'day',
                 ', ', months[dateobj.getMonth()],
                 ' ',  dateobj.getDate(),
                 ' ',  dateobj.getFullYear()
                ].join('');
      };

  result.bdformatted = dateFormatted(birthday);
  result.origbd = weekdays[birthday.getDay()]+'day';

  birthday.setFullYear(new Date().getFullYear());
  result.bdthisyear = weekdays[birthday.getDay()]+'day');
  return result;
}
//usage
var bdObj = birthDAY('1973/11/02'); // <- your timestamp here
alert(bdObj.bdformatted); //=> friday, nov 2 1973
alert(bdObj.origbd);      //=> friday
alert(bdObj.bdthisyear);  //=> wednessday