Why is adding element.getAttribute() here making my php script return error 500? [closed]

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Closed 9 years ago.

This is the code i'm using to parse a remote XML:

$xmlDoc = new DOMDocument();
$xmlDoc->load("http://www.bnr.ro/nbrfxrates.xml");

$x = $xmlDoc->documentElement;
foreach ($x->childNodes AS $item)
{
    if($item->nodeName == 'Body')
        foreach ($item->childNodes AS $body_item)
        {
            if($body_item->nodeName == 'Cube')
                foreach ($body_item->childNodes AS $cube_item)
                {                                                   
                    print " - ".$cube_item->nodeName . " : ".$cube_item->getAttribute("currency")." = ". $cube_item->nodeValue . "<br>";

                }


        }
}

If i remove the getAttribute part the script runs smoothly, but adding it causes it to return error 500.

The xml is available at the address if you want to check it out or something.

Once I activated error reporting I found the error to be: Object of class DOMText could not be converted to string

Answer 1

The problem is that childNodes is supplying both regular and text nodes. You can only call getAttribute() on the regular Element nodes (type 1). Check first that they are not text nodes before executing your print:

foreach ($body_item->childNodes AS $cube_item)
{
   // Only attempt to print the regular DOM elements                          
   if ($cube_item->nodeType == 1)
   {
     print " - ".$cube_item->nodeName . " : ".$cube_item->getAttribute("currency")." = ". $cube_item->nodeValue . "<br>";
   }
}

If in your foreach loop you were to check the nodeType of each of the childNodes, you would most likely see something similar to an alternating 3 1 3 1 3 1 for the whitespace text and regular element nodes, when you only really want the element nodes (1)

MDN has a reference list of DOM node types.

Incidentally, a quick verification of the fix with your full code produces:

 - Rate : AED = 0.9514<br>
 - Rate : AUD = 3.6518<br>
 - Rate : BGN = 2.3169<br>
 - Rate : BRL = 1.6787<br>
 - Rate : CAD = 3.5182<br>
 - Rate : CHF = 3.7628<br>
 - Rate : CNY = 0.5613<br>
 - Rate : CZK = 0.1790<br>
 - Rate : DKK = 0.6076<br>
 - Rate : EGP = 0.5726<br>
 - Rate : EUR = 4.5313<br>
 - Rate : GBP = 5.5990<br>
 - Rate : HUF = 1.6075<br>
 - Rate : INR = 0.0627<br>
 - Rate : JPY = 4.2601<br>
 - Rate : KRW = 0.3217<br>
 - Rate : MDL = 0.2836<br>
 - Rate : MXN = 0.2692<br>
 - Rate : NOK = 0.6169<br>
 - Rate : NZD = 2.8782<br>
 - Rate : PLN = 1.1019<br>
 - Rate : RSD = 0.0405<br>
 - Rate : RUB = 0.1127<br>
 - Rate : SEK = 0.5268<br>
 - Rate : TRY = 1.9469<br>
 - Rate : UAH = 0.4288<br>
 - Rate : USD = 3.4950<br>
 - Rate : XAU = 196.3192<br>
 - Rate : XDR = 5.3606<br>
 - Rate : ZAR = 0.3937<br>