Parsing Simplexml children of children

Question

I've been trying to parse this data for a while now, but I don't really understand simpleXML and how it stores/retrieves. I have the following xml:

   <ListOrderItemsResult>
    <OrderItems>
      <OrderItem>
        <QuantityOrdered>1</QuantityOrdered>
        <Title>Organic Chamomile &amp; Lavender Shea Butter CP Soap Making Kit 2 Lbs.</Title>
        <ItemPrice>
          <CurrencyCode>USD</CurrencyCode>
          <Amount>29.99</Amount>
        </ItemPrice>
        <ItemTax>
          <CurrencyCode>USD</CurrencyCode>
          <Amount>0.00</Amount>
        </ItemTax>
      </OrderItem>
      <OrderItem>
        <QuantityOrdered>1</QuantityOrdered>
        <Title>Eucalyptus &amp; Mint Organic Shea Butter CP Soap Making Kit 3 lbs.</Title>
        <ItemPrice>
          <CurrencyCode>USD</CurrencyCode>
          <Amount>32.99</Amount>
        </ItemPrice>
        <ItemTax>
          <CurrencyCode>USD</CurrencyCode>
          <Amount>0.00</Amount>
        </ItemTax>
        </ShippingDiscount>
      </OrderItem>
    </OrderItems>
    <AmazonOrderId>12134</AmazonOrderId>
  </ListOrderItemsResult>

I'm trying to convert it into csv with each OrderItem being a row. The columns are: QuantityOrdered, Title, ItemPrice, ItemTax. So far I've managed to grab the everything but ItemPrice and ItemTax, because they have children nodes and I have no idea how to access them.

Here is my code:

    $OrderItem = $xmlDocs->xpath('//a:OrderItem'); 

foreach ($OrderItem as $n) {

  foreach ($AmazonOrderId as $t) {
    $row[]=$t;
  }
   // Iterate through each child of <OrderItem> node
  $child = $xml->xpath('//a:OrderItem['.$i.']/*'); 



  foreach ($child as $value) {
    $row[] = $value;
  }
  print_r($row);



   $fs = fopen('141.csv', 'a');
   fputcsv($fs, $row);      

   $row = [];
   // Clean out array for next <item> (i.e., row)
   $i++;            // Move to next <item> (i.e., node position)

}

fclose($fs);

I have it working, but it's since I can't figure out how to get to the child of the child, nothing shows up for ItemPrice and ItemTax.

TL;DR - I'm trying to cycle through each OrderItem node and get the values of each child node and if the child node has children, I only want to get the value of the node named 'Amount'.

Answer 1

I figured out how to do it. I had to really break down simplexml to understand how the object layers so that I could figure out how to extract the data I wanted. Hopefully, this makes sense to someone, but when you're trying to extract a particular value from a SimpleXML object, you want it to read like this when you print_r():

   SimpleXMLElement Object
  (
      [0] => 0 //0 being the value you want - you can now add this to whatever variable you want once you have it down to this. 
   )

Here was the code that did it:

    //Iterate through the first node <OrderItem>
foreach ($OrderItem as $n) {           

  //Add the AmazonOrderId to the start of each line
  foreach ($AmazonOrderId as $t) {
    $row[]=$t;
  }

  $child = $xml->xpath('//a:OrderItem['.$i.']/*'); 
  // Iterate through each child of <OrderItem> node
  foreach ($child as $value) {
    //If the child has an attribute named <Amount>
    if($value->Amount[0]){
      //Iterate through and grab the value of <Amount> and post add to $row
      foreach ($value->Amount as $t) {
        $row[] = $t;
      } 
    } 
    //Else add the value to $row
    else { 
      $row[] = $value;
  }
}


$fs = fopen('141.csv', 'a');
fputcsv($fs, $row);
$row = [];
$i++;  
}
fclose($fs);