массивы — PHP: сохранение данных в древовидной структуре

Я попытался превратить комментарии сверху в пример кодирования. Измените это, чтобы удовлетворить ваши потребности:

<?php

// prepare data
$data = array(
['Process', 'MainScenario', 'Process1', 'Step1'],
[null, null, null, 'Step2'],
[null, null, null, 'Step3'],
[null, null, null, 'Step3'],
[null, null, 'Process2', 'Step1'],
[null, null, null, 'Step2'],
[null, 'SecScenario', 'Process1', 'Step1'],
[null, null, null, 'Step2'],
[null, null, 'Process2', 'Step1'],
[null, null, null, 'Step2'],
[null, null, null, 'Step3'],
);

// define class which holds the nodes
class node {
private $text = '';                                      // the text (name) of the node
private $children = array();                             // list of the children of the node

function __construct($text) {                            // constructor. sets the text
$this->text = $text;
}

function addChild(&$ref) {                               // add a child
$this->children[] = $ref;                              // store reference to child in $this->children array property
}

function getText() {                                     // get text of the node
return $this->text;                                    // retrieve textdomain
}

function getChildren() {                                 // get children of the node
return $this->children;                                // fetch & deliver array
}

function __toString() {                                  // magic function for conversion to string
return $this->getText();                               // is an alias for $this->getText
}
}

// parse the data into a tree
function buildTree($data) {
$start = array();                                         // list of all root nodes
$last = array();                                          // list of last-seen nodes on every depth

foreach ($data as $row) {                                 // iterate over all rows
$depth = 0;                                             // reset depth (start form left)
foreach ($row as $cell) {                               // iterate over all cells in the row
if (!is_null($cell) && $cell!='') {                   // empty cell? if so, ignore
if ($depth==0) {                                    // top layer?
$obj = new node($cell.' (R)');                    // this is a root node
$start[] = $obj;                                  // add to list of root nodes
$last[0] = $obj;                                  // set as root node
}
else {
$parent = null;                                   // we want to find a parent object
for ($dd = $depth-1; $dd>=0; $dd--) {             // traverse up to root
if (isset($last[$dd])) {                        // $last for this level set?
$parent = $last[$dd];                         // accept it as parent
break;                                        // do not search further
}
}

if (!is_null($parent)) {                          // parent found?
$obj = new node($cell.' ('.$depth.')');         // create new node for this entry
$parent->addChild($obj);                        // attach it to the parent
$last[$depth] = $obj;                           // set object as $last for this level
}
}
}
$depth++;                                             // increase depth (advance right)
}
}

return $start;                                            // return list of root nodes
}

// show the tree descending from a single node given
function showTree($node, $depth = 0) {                     // recursively output nodes
echo str_repeat('> ', $depth).$node->getText().PHP_EOL;  // this node
foreach ($node->getChildren() as $subnode) {             // iterate over child nodes
showTree($subnode, $depth+1);                          // recursive call for children
}
}

// execute
$rootNodes = buildTree($data);                             // build the tree
foreach($rootNodes as $node) {                             // iterate over root nodes
showTree($node);                                         // show tree for each of them
}

?>

производит:

Process (R)
> MainScenario (1)
> > Process1 (2)
> > > Step1 (3)
> > > Step2 (3)
> > > Step3 (3)
> > > Step3 (3)
> > Process2 (2)
> > > Step1 (3)
> > > Step2 (3)
> SecScenario (1)
> > Process1 (2)
> > > Step1 (3)
> > > Step2 (3)
> > Process2 (2)
> > > Step1 (3)
> > > Step2 (3)
> > > Step3 (3)

Числа в скобках являются фактическими $depth Уровень узла добавляется на. (R) обозначает корневой узел.

Посмотреть демо Вот.