在foreach PHP中进行几次迭代后，从第一个开始循环

Question

For example, I have 7 channels and 4 groups. This should be distributed in the following way:

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 

How can I distribute in This way?

I used forloop as following

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

    [1] => Array
        (
            [id] => 17
            [email] => [e-mail]
        )

    [2] => Array
        (
            [id] => 34
            [email] => [e-mail]
        )

    [3] => Array
        (
            [id] => 62
            [email] => [e-mail]
        )

)

Now,

I am having a query

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

For 4 iterations it is working fine, from 5th iteration I am getting an error:
Undefined offset: 4
How do I solve this problem?
After four iteration The loop should start from first.

Answer 1

Update: You will have to use an external variable to keep track of the current index of the group element being accessed and reset it to zero when it has gotten to the end of the group.

Is this what you are looking for?

$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"]."
"; // print out the channel and the group id

   $group_id ++;

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