从foreach开始循环，在foreach中进行几次迭代后PHP

Question

例如，我有7个通道和4个组。这应该按照以下方式分配：

Channel 1 - Group 1 
Channel 2 - Group 2 
Channel 3 - Group 3 
Channel 4 - Group 4 
Channel 5 - Group 1 
Channel 6 - Group 2 
Channel 7 - Group 3 

我该如何分配这种方式？

我用for循环如下

$groups = //array outputs the following 
Array 
(
    [0] => Array 
     (
      [id] => 10 
      [email] => [email protected] 
     ) 

    [1] => Array 
     (
      [id] => 17 
      [email] => [email protected] 
     ) 

    [2] => Array 
     (
      [id] => 34 
      [email] => [email protected] 
     ) 

    [3] => Array 
     (
      [id] => 62 
      [email] => [email protected] 
     ) 

) 

现在，

我有一个查询

foreach ($query as $key => $value) { 
    $usrSql = "UPDATE issues SET user_id = ".$usersAssigned[$key]['id']." WHERE id =".$value['id']; 
// DB updating process 
} 

对于4次迭代它工作正常，从第5次迭代，我得到一个错误：
未定义偏移量：4
我该如何解决这个问题？
四次迭代后循环应从第一次开始。

Answer 1

更新：您将不得不使用外部变量来跟踪正在访问的组元素的当前索引，并在组到达组尾部时将其重置为零。

这是你在找什么？

$channels = array("Channel 1", "Channel 2", "Channel 3", "Channel 4", "Channel 5", "Channel 6", "Channel 7"); 

$group_id = 0; 
$groups = array(array("id"=>3, "email"=>"email_1"), array("id"=>10, "email"=>"email_2"), array("id"=>6, "email"=>"email_3"), array("id"=>71, "email"=>"email_4")); 

foreach($channels as $channel) 
{ 
    echo $channel." - Group ".$groups[$group_id]["id"]."\n"; // print out the channel and the group id 

    $group_id ++; 

    if($group_id > 0 && $group_id % (count($groups)) == 0) 
     $group_id = 0; 
}