PHP array_push() 正在覆盖现有的数组元素

Question

我正在尝试将对象推入一个数组，以得到一个像这样的对象数组：

[
    {"recipient_name":"John D", "phone_number":"123456"},
    {"recipient_name":"Doe J", "phone_number":"654321"},
    {"recipient_name":"Jon Do", "phone_number":"112233"},
]

所以我在一个更大的数组上循环以获取名称和 phone 数字并将它们作为一个对象推送到这样的数组中：

$myLargerArray = pg_fetch_all($messageQuery); // This is my larger array

$size = count($myLargerArray);
for( $j = 0; $j < $size; $j++ ) {
    $myRecipientsObj->recipient_name = $myLargerArray[$j]['recipient_name'];
    $myRecipientsObj->phone_number = $myLargerArray[$j]['phone_number'];

    var_dump($myRecipientsObj); // This outputs the correct data added from [$j]

    array_push($myObjArray->message_recipients, $myRecipientsObj);

    var_dump($myObjArray->message_recipients); // The output shows array elements are being overwritten at each loop iteration
}

这是最后一个 var_dump($myObjArray->message_recipients) 的示例：

array(1) {
  [0]=>
  object(stdClass)#2 (2) {
    ["recipient_name"]=>
    string(12) "First Person"
    ["phone_number"]=>
    string(9) "112233445"
  }
}
array(2) {
  [0]=>
  object(stdClass)#2 (2) {
    ["recipient_name"]=>
    string(13) "Second Person"
    ["phone_number"]=>
    string(9) "123456789"
  }
  [1]=>
  object(stdClass)#2 (2) {
    ["recipient_name"]=>
    string(12) "Second Person"
    ["phone_number"]=>
    string(9) "123456789"
  }
}
array(3) {
  [0]=>
  object(stdClass)#2 (2) {
    ["recipient_name"]=>
    string(16) "Third Person"
    ["phone_number"]=>
    string(9) "012345678"
  }
  [1]=>
  object(stdClass)#2 (2) {
    ["recipient_name"]=>
    string(16) "Third Person"
    ["phone_number"]=>
    string(9) "012345678"
  }
  [2]=>
  object(stdClass)#2 (2) {
    ["recipient_name"]=>
    string(16) "Third Person"
    ["phone_number"]=>
    string(9) "012345678"
  }
}
array(4) {
  ... // it just overwriting the data with duplicates
}

我做错了什么导致了这个问题，我该如何解决？

Answer 1

可以直接在message_recipients前面写[]如下，

$myObjArray->message_recipients = [];
for ($j = 0; $j < $size; $j++) {
    $myRecipientsObj                 = new stdClass; // created std class object
    $myRecipientsObj->recipient_name = $myLargerArray[$j]['recipient_name'];
    $myRecipientsObj->phone_number   = $myLargerArray[$j]['phone_number'];
    $myObjArray->message_recipients[] = $myRecipientsObj;
}

应该可以。

工作demo

Answer 2

因为当你使用：

array_push($myObjArray->message_recipients, $myRecipientsObj);

您正在将对该对象的引用推送到数组中，然后当您在随后的循环中更改该对象时，您实际上更改了数组中每个元素的内容。要解决此问题，您需要将对象的副本推送到数组中：

array_push($myObjArray->message_recipients, clone $myRecipientsObj);

Demo on 3v4l.org

Answer 3

$myObjArray->message_recipients[] = \DeepCopy\deep_copy($myRecipientsObj);

PHP array_push() 正在覆盖现有的数组元素

PHP array_push() is overwriting existing array elements

php

arrays

loops

multidimensional-array

array-push