php键未定义，但是有键

Question

I am making my own array from another one, using email field as key value. If there is more results with same email I am amking array_push to existing key.

I am getting always data in my array (with email) and here is the example

Input data

Example data

$saved_data = [
    0 => ['custom_product_email' => 'test@test.com',...],
    1 => ['custom_product_email' => 'test@test.com',...],
    2 => ['custom_product_email' => 'bla@test.com',...],
    3 => ['custom_product_email' => 'bla@test.com',...],
    ...
];

Code

$data = [];
foreach ($saved_data as $products) {
  $curVal = $data[$products->custom_product_email];
  if (!isset($curVal)) {
    $data[$products->custom_product_email] = [];
  }
  array_push($data[$products->custom_product_email], $products);
}

Error

I am getting error Undefined index: test@test.com and if I debug my array, there is key with value of 'test@test.com' , so key is defined (!)

so var $curVal key is undefined

Result

So the goal of foreach is to filter all objects in array with same email, here is the example:

$data = [
  'test@test.com' => [
    0 => {data},
    1 => {data},
    ...
  ],
  'bla@test.com' => [
    0 => {data},
    1 => {data},
    ...
  ],

];

Answer 1

Did you not see the error message?

Parse error: syntax error, unexpected '{' in ..... from this code

$saved_data = [
    0 => {'custom_product_email' => 'test@test.com',...},
    1 => {'custom_product_email' => 'test@test.com',...},
    2 => {'custom_product_email' => 'bla@test.com',...},
    3 => {'custom_product_email' => 'bla@test.com',...},
    ...
];

Change the {} to [] to correctly generate the array.

$saved_data = [
    0 => ['custom_product_email' => 'test@test.com',...],
    1 => ['custom_product_email' => 'test@test.com',...],
    2 => ['custom_product_email' => 'bla@test.com',...],
    3 => ['custom_product_email' => 'bla@test.com',...],
    ...
];

Your next issue is in this code

$data = [];
foreach ($saved_data as $products) {
  $curVal = $data[$products->custom_product_email];
//          ^^^^^

$data is an empty array that you initialised 2 lines above, so it does not contain any keys or data!

Answer 2

this line $curVal = $data[$products->custom_product_email]; is useless and is the one provoking the error: you just initialized $data as an empty array, logically the index is undefined.

You should test directly if (!isset($data[$products->custom_product_email])) {

Then explanation: there is a fundamental difference between retreiving the value of an array's index which is undefined and the same code in an isset . The latter evaluating the existence of a variable, you can put inside something that doesn't exist (like an undefined array index access). But you can't store it in a variable before the test.

Answer 3

Check, if $data[$products->custom_product_email] is already set in $data array

Try This code

$data = [];

foreach ($saved_data as $products) {
  $curVal = isset($data[$products->custom_product_email]) ? $data[$products->custom_product_email] : null;
  if (!isset($curVal)) {
    $data[$products->custom_product_email] = [];
  }
  array_push($data[$products->custom_product_email], $products);
}