如何從週數

Question

獲取週數這種格式獲得首發日期：

$weeknumber = date('W', strtotime('10-02-2015')); 

如何從這個weeknumber開始日期。

Answer 1

使用此

你需要改變這樣的strtotime('10-02-2015'))

$date_string = "2012-10-18"; 
$weeknumber = date("W", strtotime($date_string)); 

//get the date from week number 

isodate

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

Answer 2

您可以使用此

echo $weeknumber = date('W', strtotime('18-10-2012')); 
    $gendate = new DateTime(); 
    $gendate->setISODate(2015,$weeknumber,4); //year , week num , day 
    echo $gendate->format('d-m-Y'); //"prints" 

Answer 3

不要功能與DateTime類混合strtotime()和date()功能。它可沒有他們簡單地完成，而用只有DateTime，如：

$date = new DateTime('10-02-2015'); 
$date->setISODate($date->format('o'), $date->format('W')); 
echo $date->format('d-m-Y'); 

demo