how to read XML id's with value and update it by PHP

Question

My XML:

<WorkingTime>
    <FromTime>08:00</FromTime>
    <ToTime>11:00</ToTime>
    <Name>Izpit</Name>
    <Owner>Marko</Owner>
    <Category>
        <School Professor="111" Room="1" Subject="882" />
    </Category>
</WorkingTime>

<Professors>
    <Professor email="xxx" id="111" code="String">Name 1</Professor>
    <Professor email="xxx" id="222" code="String">Name 2</Professor>
    <Professor email="xxx" id="333" code="String">Name 3</Professor>
</Professors>
<Rooms>
    <Room id="1">IA-301</Room>
    <Room id="2">A-302</Room>
    <Room id="3">A-303</Room>
    <Room id="4">A-304</Room>
    <Room id="5">A-305</Room>
    <Room id="6">A-306</Room>

</Rooms>
<Subjects>
    <Subject id="881">Vaje</Subject>
    <Subject id="882">Kolokvij</Subject>
    <Subject id="883">Predmet</Subject>
    <Subject id="884">Izpit</Subject>
</Subjects>

How can I in php now print Professor.

I can get id like:

$professor = $workingTime->Category->School->attributes()->Professor;
$room      = $workingTime->Category->School->attributes()->Room;
$subject   = $workingTime->Category->School->attributes()->Subject;

but how to now get value:

I try this but is empty:

echo $xml->Professors->Professor[$professor];

And how can I update values.

I want to save:

<Category>
    <School Professor="222" Room="2" Subject="883" />
</Category>

I am using dom_import_simplexml and simplexml_load_file.

score 2 · Answer 1 · edited May 23 '17 at 12:28

Professor is an element, not an attribute. Therefore using attributes() to access that element makes no sense, does not work and - as you clearly write already in your question - gets you an "empty" element.

On the other hand, id is an attribute and could be accessed that way.

However for both cases I would suggest you to follow the description given in the base SimpleXML examples in the PHP manual which are a good entry level tutorial:

Basic SimpleXML usage

Here on Stackoverflow, you need to search for the concrete problems btw. not ask about all problems alltogether, e.g. Q&A material like:

I hope this helps you obtaining the information you're looking for. Let me know if you find better Q&A here on site regarding the subjects you need to cover and as well if you're missing something.

how to read XML id's with value and update it by PHP

1 Answers1