Special characters () appear in front of the XML tag

Question

I am reading two XML files but created on different computers. This first was created on my computer:

<?xml version="1.0" encoding="UTF-8"?> ...

Already this below with same content appears a sequence of special characters () before the tag xml. Behold:

<?xml version="1.0" encoding="UTF-8"?> ...

Even copying the contents of one file and pasting in another, still at the time of using the new SimpleXMLElement($contentFile) remains the same.

As these strange characters appear, an error occurs:

Warning: Simplexmlelement::__Construct(): Entity: line 1: parser error : Start tag expected, '<' not found in C: wamp64 www...

At first I thought to remove these characters using regular expression, but I thought maybe there is already something ready in relation to this (which I still don’t know);

How can I fix this problem?

Answer 1

The characters  indicate that the document was saved with "UTF-8 with GOOD", when you were supposed to save "UNWELL".

How to resolve in the application

Note: in the examples I used simplexml_load_string, but both he and the simplexml_load_file returns a SimpleXMLElement:

SimpleXMLElement simplexml_load_string ( string $data [, string $class_name = "SimpleXMLElement" [, int $options = 0 [, string $ns = "" [, bool $is_prefix = false ]]]] )

I have no way to state which document it is, you can try to decode the XML content before "parse":

$data = file_get_contents($url);
$data = utf8_decode($data);

$xml = simplexml_load_string($data);

...

$xml->asXML();

Or decode and encode again (if you have a problem with XML being UTF-8 in the header):

$data = file_get_contents($url);
$data = utf8_decode($data);
$data = utf8_encode($data);

$xml = simplexml_load_string($data);

...

$xml->asXML();

You can choose to try using the trim (this by the way was the only one that worked for me):

$data = file_get_contents('A.xml');

$data = trim($data); //Remove os espaçamentos incluindo o "BOM"

$xml = simplexml_load_string($data);

...

$xml->asXML();

If none works can try the substr with strpos thus:

$data = file_get_contents($url);

$data = substr($data, strpos($data, '<'));

$xml = simplexml_load_string($data);

...

$xml->asXML();

Even if you fail, it might match utf8_decode and utf8_encode again:

$data = file_get_contents($url);

$data = substr($data, strpos($data, '<'));

$data = utf8_decode($data);
$data = utf8_encode($data);

$xml = simplexml_load_string($data);

...

$xml->asXML();

How to resolve with text editors/processors

If you have access to these .xml you can edit them using the Notepad++:

Or sublimetext: