Passing a multidimensional array through hidden input via POST

Question

So I researched online to see how I can pass an array which I POST through form.

Here's what I did.

 $itemsArr = array();
 while ($row = $result->fetch_assoc()) {
 $totalPrice += $row['item_price'];
 $totalItemsOnCart += $row['quantity'];
 $itemId = $row['item_idPK'];
 $itemName = $row['item_name'];
 $itemPrice = $row['item_price'];
 $itemQty = $row['quantity'];
 $itemsArr[] = array($userId, $itemId, $itemQty);
 echo "<tr>";
 echo "<td>".$itemId."</td>";
 echo "<td>".$itemName."</td>";
 echo "<td>".$itemPrice."</td>";
 echo "<td>".$itemQty."</td>";
 echo "</tr>"; 
 }

Then, I used the foreach loop to iterate through the multidimensional array.

echo "<form class = 'BreadCode' action='Function_Cart.php' method='POST'>";
foreach($itemsArr as $value){
 print_r($value);
 echo '<input type="hidden" name="itemsArr[]" value="'. $value. '">';
}
 echo "<input type='hidden' name='userId' value='$userId'>";
 echo "<input type='hidden' name='itemId' value='$itemId'>";
 echo "<input type='hidden' name='quantity' value='$itemQty'>";
 echo "<input class='PayButton' type='submit' name='Btn-pay' value='Pay'>";
 echo "</form>";

I keep getting an "Array to string conversion" error with or without the echo for the hidden input within the foreach() loop

I haven't really tried sending an array via form through POST method in the past. I just don't know how to go about this.

Below is the result of print_r()

Array ( [0] => 5112 [1] => 105 [2] => 2 ) 
Array ( [0] => 5112 [1] => 104 [2] => 1 )

Please help.

Thank you.

• urfusion: you can pass it asjson. before foreach <input type="hidden" name="itemsArr" value="'<?php echo json_encode($itemsArr ); ?>. '">

Answer 1

You just need to encode array to json and decode it on action page

echo '<input type="hidden" name="itemsArr" value="'.json_encode($itemsArr). '">';

And at your action Page just decode it

$itemsArr = json_decode($_POST['itemsArr'],true)

• heisenberg: Thanks. However, I have one problem when I decode it. It returns nothing when I try to echo var_dump($itemsArr) or print_r($itemsArr)
• Bhupendra Mistry: inspect element and check the input tag contain proper json data or not try to just print $_POST['itemsArr'] should it print something or note?

Answer 2

There is no need for place foreach and increase execution time. You can simply do that by using json_encode.

echo "<form class = 'BreadCode' action='Function_Cart.php' method='POST'>";
echo '<input type="hidden" name="itemsArr" value="' . json_encode($itemsArr) . '">';
echo "<input type='hidden' name='userId' value='$userId'>";
echo "<input type='hidden' name='itemId' value='$itemId'>";
echo "<input type='hidden' name='quantity' value='$itemQty'>";
echo "<input class='PayButton' type='submit' name='Btn-pay' value='Pay'>";
echo "</form>";

• heisenberg: Thanks. There's just one problem. I can't seem to get the value when I try json_decode($_POST['itemsArr'],true); It returns nothing or null.