使用php unset引用foreach循环中的项

Question

I return this array of objects from an API call like so. Note that $result is an array of arrays with $result[data] holding todo list objects and result[success] holding status of API call:

        array(9) { [0]=> object(stdClass)#3 (5) { ["todo_id"]=> string(10) "1480430478" ["title"]=> string(13) "Check Printer" ["description"]=> string(8) 
    "Room 233" ["due_date"]=> string(10) "11/29/2016" ["is_done"]=> string(4) "true" } [1]=> object(stdClass)#4 (5) { ["todo_id"]=> string(10) "148043046" ["title"]=> string(18) "Doctor Appointment" ["description"]=> string(7)
     "@4pm. " ["due_date"]=> string(10) "11/30/2016" ["is_done"]=> string(4) "true" }
        etc..

I sort the array with usort fine and then I want to resort on the "is_done" field and put them at bottom of todo list in date order. The php to do this is :

//Sort by is_done
   foreach($result[data] as $arrayElement ) {
       foreach($arrayElement as $valueKey => $value) {
          if(($valueKey == 'is_done') && ($value == 'true')){
              $temp = $arrayElement;
            //delete this particular object from the $array
               unset($result[data][$arrayElement]);
               array_push($result[data], $temp);
           } 
        }
   }

The problem I am having is my completed items are now at the end of the array but they are also still in their original position. The unset is not working. I have tried all variations on referencing the $result[data] item to no avail. This is probably something simple but I need some help if possible. Googling and checking this site shows no examples of unset in this type of situation. Thanks in advance.

Update: after applying colburton's solution the API is now returning this data structure:

 object(stdClass)#3 (6) { ["2"]=> object(stdClass)#4 (5) { ["todo_id"]=> int(1480698596) ["title"]=> string(7) "Test #4" ["description"]=> string(4) "test" ["due_date"]=> string(10) "12/02/2016" ["is_done"]=> string(5) "false" } ["3"]=> object(stdClass)#5 (5) { ["todo_id"]=> string(10) "1480617975" ["title"]=> string(13) "Check Printer" ["description"]=> string(4) 
"Test" ["due_date"]=> string(10) "12/06/2016" ["is_done"]=> string(5) "false" } ["5"]=> object(stdClass)#6 (5) { ["todo_id"]=> int(1481136023) ["title"]=> string(9) "Todo item" ["description"]=> string(7) "test123" ["due_date"]=> string(10) "01/19/2017" ["is_done"]=> string(5) "false" } etc...

At the end of the call i do a

//json_decode the result
        $result = @json_decode($result);

        //check if we're able to json_decode the result correctly
        if ($result == false || isset($result->success) == false) {
            throw new Exception('Request was not correct');
        }

        //if there was an error in the request, throw an exception
        if ($result->success == false) {
            throw new Exception($result['errormsg']);
        }

        //if everything went great, return the data
        return $result->data;
  } 

and then in main program I reference $result as

$result = $todo_items[0];

And that is where fatal error occurs now.

Update II: Wanted to add that you then need to reindex the array

$result['data'] = array_values($result['data']);

I read here that this is a bug in json_decode. Thanks for the help....

Answer 1

Please use quotes around your array indices. This unsets what you want:

foreach ($result['data'] as $idx => $arrayElement) {
    foreach ($arrayElement as $valueKey => $value) {
        if (($valueKey == 'is_done') && ($value == 'true')) {
            $temp = $arrayElement;
            //delete this particular object from the $array
            array_push($result['data'], $temp);
            unset($result['data'][$idx]);
        }
    }
}