How to get date from week number & day number and year?

问题

I'm trying to get the date from the week number, day number and year.

For eg:

week number = 52   
day number = 4 (of week 52)  
year = 2013  

In this case, the date should be 26-12-2013.

How can I do it using PHP? I've already tried with strtotime(), but I'm confused about the formats. Can someone help?

回答1:

Make use of setISODate()

<?php
$gendate = new DateTime();
$gendate->setISODate(2013,52,4); //year , week num , day
echo $gendate->format('d-m-Y'); //"prints"  26-12-2013

回答2:

Try this code.

 <?php

    function change_date($week_num, $day) {
      $timestamp    = strtotime(date('Y') . '-W' . $week_num . '-' . $day);
      return $timestamp;
    }
   $timestamp = change_date(52, 4);
    echo date('d-m-Y', $timestamp);
?>

来源：https://stackoverflow.com/questions/20780834/how-to-get-date-from-week-number-day-number-and-year