PHP：将数据与来自单个阵列的共享密钥组合到新阵列中

Question

I have this array:

array(5) {
  [0]=>
  array(4) {
    ["productCode"]=>
    string(4) "X001"
    ["productUPC"]=>
    string(3) "261"
    ["productTextSeq"]=>
    string(1) "1"
    ["productTxtVal"]=>
    string(5) "Text1"
   }
  [1]=>
  array(4) {
    ["productCode"]=>
    string(4) "X001"
    ["productUPC"]=>
    string(3) "261"
    ["productTextSeq"]=>
    string(1) "2"
    ["productTxtVal"]=>
    string(5) "Text2"
   }
  [2]=>
  array(4) {
    ["productCode"]=>
    string(4) "X001"
    ["productUPC"]=>
    string(3) "261"
    ["productTextSeq"]=>
    string(1) "3"
    ["productTxtVal"]=>
    string(5) "Text3"
   }
  [3]=>
  array(4) {
    ["productCode"]=>
    string(4) "X002"
    ["productUPC"]=>
    string(3) "262"
    ["productTextSeq"]=>
    string(1) "1"
    ["productTxtVal"]=>
    string(5) "Text1"
   }
  [4]=>
  array(4) {
    ["productCode"]=>
    string(4) "X002"
    ["productUPC"]=>
    string(3) "262"
    ["productTextSeq"]=>
    string(1) "2"
    ["productTxtVal"]=>
    string(5) "Text2"
   }
}

With the above input, I want the output array to look like this:

array(2) {
  [0]=>
  array(3) {
    ["productCode"]=>
    string(4) "X001"
    ["productUPC"]=>
    string(3) "261"
    ["productTxtVal"]=>
    string(17) "Text1 Text2 Text3"
   }
  [1]=>
  array(3) {
    ["productCode"]=>
    string(4) "X002"
    ["productUPC"]=>
    string(3) "262"
    ["productTxtVal"]=>
    string(11) "Text1 Text2"
   }
}

The resulting array does not need the productTextSeq key, just the combined values of productTextVal, when the productCode is the same. I've searched SO for examples of this but it seems every example I've found are based on multiple input arrays. I know I can brute force this with nested foreach functions but would love a more elegant solution.

Answer 1

I ended up just doing it the brute force method, here is my solution if anyone's interested:

$productData = array();
$sortedData = array();
$comments = '';
$saveKey = '';
$appendComment = false;
$idx = 0;

foreach ($data as $key=>$value) {

    foreach ($value as $k=>$v) {
        if ($k == 'productCode') {
            if ($v == $saveKey) {
                $appendComment = true;
            } else {
                $appendComment = false;
                $saveKey = $v;
                if ($idx !== 0) { // Don't write to array on first iteration!
                    $productData['productTxtVal'] = $comments;
                    $sortedData[] = $productData;
                }
            }
        }

        if ($k == 'productTxtVal') {
            if ($appendComment == true) {
                $comments .= ' ' . trim($v);
            } else {
                $comments = trim($v);
            }
        }
    }

    $productData = $value;
    $idx++;
}

Not "elegant" but it works. I also have a check after this logic in case only one productCode is in the original array, as it won't be written to the $sortedData array since the key never changes.

Answer 2

The following code assumes you control the contents of the original data array (due to risk of injection using extract() function) and that no 2 items with the same productCode have the same productTextSeq .

$products = [];
foreach ($data as $item) {
    // extract contents of item array into variables
    extract($item);
    if (!isset($products[$productCode])) {
        // create product array with code, upc, text as array
        $products[$productCode] = compact('productCode', 'productUPC') + ['productTxtVal' => []];
    }
    // add text value to array with sequence as index
    $products[$productCode]['productTxtVal'][$productTextSeq] = $productTxtVal;
}

$products = array_values( // ignore array keys
    array_map(function($product) {
        ksort($product['productTxtVal']); // sort text as array by index/ sequence
        $product['productTxtVal'] = implode(' ', $product['productTxtVal']); // implode into string
        return $product;
    }, $products)
);

You can run the code here: https://repl.it/BWQL