Forcing a SimpleXML Object to a string, regardless of context

Question

Let's say I have some XML like this

<channel>
  <item>
    <title>This is title 1</title>
  </item>
</channel>

The code below does what I want in that it outputs the title as a string

$xml = simplexml_load_string($xmlstring);
echo $xml->channel->item->title;

Here's my problem. The code below doesn't treat the title as a string in that context so I end up with a SimpleXML object in the array instead of a string.

$foo = array( $xml->channel->item->title );

I've been working around it like this

$foo = array( sprintf("%s",$xml->channel->item->title) );

but that seems ugly.

What's the best way to force a SimpleXML object to a string, regardless of context?

I've submitted multiple requests to PHP to implement something similar to SOAP_SINGLE_ELEMENT_ARRAYS for this, and would encourage others to do the same. SOAP_SINGLE_ELEMENT_ARRAYS forces elements that /could/ hold more than one string to be parsed always as just strings. Of course as others mentioned you need to know what you're getting back, but time and time again I've run into issues with .NET SOAP servers that the WSDL for ( by .NET's "magic" defaults ) prototyped every string as either mixed or an array of strings. Instead of current()'ing or typecasting, the bit just gives back a string — conrad10781, Dec 09 '17 at 20:37

Aron Rotteveel · Accepted Answer · 2009-01-06T14:23:32.163

154

Typecast the SimpleXMLObject to a string:

$foo = array( (string) $xml->channel->item->title );

The above code internally calls __toString() on the SimpleXMLObject. This method is not publicly available, as it interferes with the mapping scheme of the SimpleXMLObject, but it can still be invoked in the above manner.

edited Jan 06 '09 at 14:23

answered Jan 06 '09 at 14:01

Aron Rotteveel

81,193
17
104
128

That's cleaner than using a sprintf. I like it – Mark Biek Jan 06 '09 at 14:10
5

Note that using a function that accepts string arguments will automatically do this type casting (e.g. echo, str_replace, substr). – Ross Jan 06 '09 at 14:33
Thanks Aron, I thought a typecast was the way to do this but it just didnt feel right. Now that I know the _toString method is private it makes sense. – Neil Aitken Aug 12 '09 at 11:03
3

$foo = (string) $xml->channel->item->title; is what I was looking for, since I don't need an array. Thanks. – Drazisil Aug 01 '12 at 17:36
1

+100 you just made my evening! Im new to SimpleXMLObject the vars I had extracted from it were 'printing' fine to the screen but failing my DB query...sigh! Since when was PHP strictly typed? ;-) – megaSteve4 Oct 28 '12 at 19:44
1

@megaSteve4 "Since when was PHP strictly typed?" - it's precisely because it's not that this needs to happen: most functions don't have a defined type context, so cannot implicitly cast to that type. Of course, they can *explicitly* cast their input params, which is why `substr` et al work. It's safer to do the cast as early as possible though, so you know all functions will see the data they expect. – IMSoP Feb 21 '13 at 10:13

score 23 · Answer 2 · answered Feb 04 '09 at 20:06

23

You can use the PHP function

strval();

This function returns the string values of the parameter passed to it.

answered Feb 04 '09 at 20:06

Zaje

2,281
5
27
39

3

@Mark Biek: It does work on objects that have `__toString()` implemented and especially in this questions case in specific, it works very well with objects of type `SimpleXMLElement`. You can compare it with the `string` cast in the accepted answer. `strval()` is a handy callback function often in conjunction with [`array_map()`](http://php.net/array_map) and [`iterator_to_array($simpleXMLElement, false)`](http://php.net/iterator_to_array) or `SimpleXMLElement::xpath()`. – hakre Feb 21 '13 at 11:21

Mixed Case · Answer 3 · 2013-02-01T06:18:43.893

9

There is native SimpleXML method SimpleXMLElement::asXML Depending on parameter it writes SimpleXMLElement to xml 1.0 file or just to a string:

$xml = new SimpleXMLElement($string);
$validfilename = '/temp/mylist.xml';
$xml->asXML($validfilename);    // to a file
echo $xml->asXML();             // to a string

edited Feb 01 '13 at 06:18

answered Feb 01 '13 at 06:03

Mixed Case

91
1
3

I get call to an undefined function asXML so I'm guessing this is out of date now? – Eoin Jun 08 '19 at 16:16
1

@Eoin Hmm... Just tested my example, it's still works fine with native php 7.3 installation – Mixed Case Nov 03 '19 at 05:58
I must have had a different problem them. My apologies. I fixed my issue now :) – Eoin Nov 04 '19 at 13:17

score 3 · Answer 4 · answered Aug 13 '12 at 08:25

3

Another ugly way to do it:

$foo = array( $xml->channel->item->title."" );

It works, but it's not pretty.

answered Aug 13 '12 at 08:25

Mikepote

6,042
3
34
38

score 3 · Answer 5 · answered Sep 07 '16 at 16:24

The accepted answer actually returns an array containing a string, which isn't exactly what OP requested (a string). To expand on that answer, use:

$foo = [ (string) $xml->channel->item->title ][0];

Which returns the single element of the array, a string.

score 2 · Answer 6 · answered Sep 29 '17 at 15:40

2

Not sure if they changed the visibility of the __toString() method since the accepted answer was written but at this time it works fine for me:

var_dump($xml->channel->item->title->__toString());

OUTPUT:

string(15) "This is title 1"

answered Sep 29 '17 at 15:40

But those new buttons though..

21,377
10
81
108

score 2 · Answer 7 · answered Jul 11 '11 at 21:27

To get XML data into a php array you do this:

// this gets all the outer levels into an associative php array
$header = array();
foreach($xml->children() as $child)
{
  $header[$child->getName()] = sprintf("%s", $child); 
}
echo "<pre>\n";
print_r($header);
echo "</pre>";

To get a childs child then just do this:

$data = array();
foreach($xml->data->children() as $child)
{
  $header[$child->getName()] = sprintf("%s", $child); 
}
echo "<pre>\n";
print_r($data);
echo "</pre>";

You can expand $xml-> through each level until you get what you want You can also put all the nodes into one array without the levels or just about any other way you want it.

score 1 · Answer 8 · answered Jul 04 '17 at 15:04

1

Try strval($xml->channel->item->title)

answered Jul 04 '17 at 15:04

Ariel Ruiz

163
2
6

score 0 · Answer 9 · answered Nov 23 '18 at 09:54

There is native SimpleXML method SimpleXMLElement::asXML Depending on parameter it writes SimpleXMLElement to xml 1.0 file, Yes

$get_file= read file from path;
$itrate1=$get_file->node;
$html  = $itrate1->richcontent->html;


echo  $itrate1->richcontent->html->body->asXML();
 print_r((string) $itrate1->richcontent->html->body->asXML());

score 0 · Answer 10 · answered May 03 '20 at 15:36

0

Just put the ''. before any variable, it will convert into string.

$foo = array( ''. $xml->channel->item->title );

answered May 03 '20 at 15:36

Krishan Kumar

394
4
13

score -1 · Answer 11 · answered Jul 17 '17 at 19:26

The following is a recursive function that will typecast all single-child elements to a String:

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// FUNCTION - CLEAN SIMPLE XML OBJECT
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function cleanSimpleXML($xmlObject = ''){

    // LOOP CHILDREN
    foreach ($xmlObject->children() as $child) {

        // IF CONTAINS MULTIPLE CHILDREN
        if(count($child->children()) > 1 ){

            // RECURSE
            $child = cleanSimpleXML($child);

        }else{

            // CAST
            $child = (string)$child;

        }

    }

    // RETURN CLEAN OBJECT
    return $xmlObject;

} // END FUNCTION

Forcing a SimpleXML Object to a string, regardless of context

11 Answers11

Linked

Related