获取XML标记和属性直至n级

Question

Is it possible to get tag names and attributes names with values upto n levels. For example,

File 1:

<?xml ?>
<data>
    <student>
        <std>4th</std>
        <student>Alex</student>
        <division name="A" />
    </student>
</data>

File 2:

<?xml ?>
<data>
    <students>
        <student>
            <std>4th</std>
            <student>Alex</student>
            <division name="A" />
        </student>
        <student>
            <std>5th</std>
            <student>Alice</student>
            <division name="D" />
            <subject>Drawing</subject>
        </student>
    </students>
</data>

File 3:

<?xml ?>
<data>
    <students>
        <student>
            <std>4th</std>
            <student>Alex</student>
            <division name="A" />
        </student>
        <student>
            <std>5th</std>
            <student>Alice</student>
            <division name="D" />
            <subject>Drawing</subject>
        </student>
    </students>
    <students>
        <student>
            <std>4th</std>
            <student>Alex</student>
        </student>
        <student>
            <std>5th</std>
            <student>Alice</student>
            <division name="D" />
            <subject>Drawing</subject>
        </student>
        <student>
            <std>5th</std>
            <student>Alice</student>
            <division name="D" />
            <subject>
                <sub1>Drwaing</sub1>
                <sub1>Maths</sub1>
            </subject>
        </student>
    </students>
</data>

Above are examples file 1 is simple file, file 2 is with more tags and file 3 is more longer than other. So my basic question is that XML file format is not predefined it's may be anything just like above examples. So is it possible to get tags names, attribute names with its values in php? If yes then how?

I already tried some solutions with $xml->children()->children() and $child->getName() i didn't find any perfect way normally it is good for 2 level or 3 level but no solution for N level xml tags.

I tried as below :

$xml='<person>
    <child role="son">
        <child role="daughter"/>
    </child>
    <child role="daughter">
        <child role="son">
            <child role="son"/>
            <name role="trainer">
                <nickname role="assistant">Nic</nickname>
                <fname>Nicolas</fname>
                <lname>Johnson</lname>
                <hobby>
                    <sport>
                        <game>
                            <name>Cricket</name>
                            <name type="male">Hockey</name>
                            <name type="national" />
                        </game>
                    </sport>
                </hobby>
            </name>
        </child>
    </child>
    <child role="daughter">
        <child role="son">
            <child role="son"/>
            <name role="student">Jessika</name>
        </child>
        <child role="son">
            <child role="son"/>
            <names>
                <name>Nick</name>
            </names>
        </child>
    </child>
    <child role="daughter">
        <child role="son">
            <child role="son"/>
        </child>
        <child role="son">
            <child role="son"/>
            <child role="son"/>
            <name>Tom</name>
        </child>
        <child role="son">
            <child role="son"/>
            <child role="son"/>
            <name>John</name>
        </child>
    </child>
</person>';
$xml = new SimpleXMLElement($xml);
foreach ($xml->children() as $second_gen) {
    echo '<br> role=' . $second_gen['role'];
    foreach ($second_gen->children() as $third_gen) {
        echo '<br> role=' . $third_gen['role'];
        foreach ($third_gen->children() as $fourth_gen) {
            echo '<br> role=' . $third_gen['role'];
        }
    }
}

Note that file1, file2 & file3 example are different and above are different so don't confused i already mentioned that XML file & format are not predefined it may be anything any level.

In above example i tried with 3 foreach loops but when it is upto N level then it's not working properly. I want to do totally dynamically. Is it possible?

If you have more better ideas or ways then you can share. Thanks for giving your valuable time.

I want to do following.

I want to get some values like student name, fees, standard, stream, subjects, division and other normal details from XML. Now the main problem is XML format is not predefined it may be like as above examples that i mentioned. It is totally dynamic and i want to store in table as per the tags and/or attribute values.

I hope are useful to understand what i want to say if any doubts then feel free to ask. Thanks.

Answer 1

Xpath expressions allow you to fetch nodes (and values) from the XML document.

$xml = <<<'XML'
<data>
    <student>
        <std>4th</std>
        <student>Alex</student>
        <division name="A" />
    </student>
</data>
XML;

$data = new SimpleXMLElement($xml);

foreach($data->xpath('//student[student]') as $student) {
  var_dump(
    [
      (string)$student->std,
      (string)$student->student,
      (string)$student->division['name']
    ]
  );
}

Output:

array(3) {
  [0]=> 
  string(3) "4th"
  [1]=>
  string(4) "Alex"
  [2]=> 
  string(1) "A" 
}

The Xpath Expression

• any student element node in the document...
  //student
• ... that has a student child element:
  //student[student]

Xpath expressions are quite powerful. For example you could fetch any student that has no student ancestor node, too:

//student[not(ancestor::student)]