如何查找給定日期所屬的一週中的第一天？

Question

可能重複：
Get first day of week in PHP?

給出一個時間戳我需要找到第一天時間戳屬於周。

例如

$format = "first day of week"; 

//convert to time 
$time = strtotime("2011-07-01 00:00:00"); 

//format the time to the first day of the week 
$date = strtotime($format,$time); 

//Put the first day of the week into a pretty format 
$weekStartDate = date("Y-m-d",$date); 

本週開始應該在此刻它走了可怕的錯誤等於2011-06-27和1970-01-01等於這表明我的「一週的第一天」的格式是無效的。

任何想法，將不勝感激，謝謝，

Answer 1

$time = strtotime("2011-07-01 00:00:00"); 

$weekStartDate = date('Y-m-d',strtotime("last Monday", $time)); 

Answer 2

測試：

$time=[Your Request Time]; 

$dayofweek = date("w",strtotime($time)); 

if($dayofweek != 0 ) 

    $firstdayOfWeek = strtotime($time . " - " . $dayofweek . " days "); 

else 

    $firstdayOfWeek = strtotime($time);