问题
I have a table like
id catagory suboff
1 software 0
2 programming 1
3 Testing 1
4 Designing 1
5 Hospital 0
6 Doctor 5
7 Nurses 5
9 Teaching 0
10 php programming 2
11 .net programming 2
How to write a code to get all these information in a multidimensional array based on the suboff as follows,
-software
--programming
---php programming
--- .net programming
--testing
--designing
-hospital
--doctor
--nurses
-teaching
回答1:
Assuming MySQL as your DB engine:
// We'll need two arrays for this
$temp = $result = array();
// Get the data from the DB
$table = mysql_query("SELECT * FROM table");
// Put it into one dimensional array with the row id as the index
while ($row = mysql_fetch_assoc($table)) {
$temp[$row['id']] = $row;
}
// Loop the 1D array and create the multi-dimensional array
for ($i = 1; isset($temp[$i]); $i++) {
if ($temp[$i]['suboff'] > 0) {
// This row has a parent
if (isset($temp[$temp[$i]['suboff']])) {
// The parent row exists, add this row to the 'children' key of the parent
$temp[$temp[$i]['suboff']]['children'][] =& $temp[$i];
} else {
// The parent row doesn't exist - handle that case here
// For the purposes of this example, we'll treat it as a root node
$result[] =& $temp[$i];
}
} else {
// This row is a root node
$result[] =& $temp[$i];
}
}
// unset the 1D array
unset($temp);
// Here is the result
print_r($result);
Use references for a job like this.
回答2:
Demo: http://ideone.com/vk4po
$array = array(
array('1','software','0'),
array('2','programming','1'),
array('3','Testing','1'),
array('4','Designing','1'),
array('5','Hospital','0'),
array('6','Doctor','5'),
array('7','Nurses','5'),
array('9','Teaching','0'),
array('10','php programming','2'),
array('11','.net programming','2')
);
function menu_sort($results, $master = 0)
{
$open = array();
$return = NULL;
foreach($results as $result)
{
if($result[2] == $master){
if(!$open){
$return .= '<ul>';
$open = true;
}
$return .= '<li>'.$result[1];
$return .= menu_sort($results, $result[0]);
$return .= '</li>';
}
}
if($open)
$return .= '</ul>';
return $return;
}
echo menu_sort($array);
Result...
software programming php programming .net programming Testing Designing Hospital Doctor Nurses Teaching
回答3:
The way I would do that:
First you need to parse this table. I assume you can do it yourself; if not, Google "regular expressions", they are your friends.
The data structure you are working with is a classical tree. You will need two arrays to work with it. First is an array of nodes,
$nodes, where the keys are the node IDs and values are node names, and$links, where each key is a parent node and each value is an array of children ($links[$id][] = $subofffor each element would suffice).Now you have to recursively descent the tree you have. You introduce a function with a signature like this:
function print_node( $nodeID, $level = 1 )This function should print the node itself (info stored in $nodes) with $level padding dashes and call itself to render all children nodes. They will in turn render all their subnodes, etc. You just have to call this function for top-level nodes.
回答4:
This class converst a flat category array into a structured tree array:
<?php
/**
* Creates a structured tree out of a flat category list
*/
class CategoryTree {
/**
*
* @var array
*/
protected $categories = array();
/**
*
* @var array
*/
protected $tree = array();
/**
* Default constructor
* @param array $categories
*/
function __construct(array $categories) {
$this->categories = $categories;
}
/**
* Process a subtree
* @param array $categories
* @param integer $parentId
* @return array
*/
protected function getSubtree(array $categories, $parentId = 0) {
$tree = array();
foreach($categories as $category) {
if($category['suboff'] == $parentId) {
$tree[$category['id']] = $category;
$tree[$category['id']]['children'] = $this->getSubtree($categories, $category['id']);
}
}
return $tree;
}
/**
* Get the category tree as structured array
* @return array
*/
public function getTree() {
if(empty($this->tree)) {
$this->tree = $this->getSubtree($this->categories, 0);
}
return $this->tree;
}
/**
* Get the category tree as string representation
* @return string
*/
public function __toString() {
return "<pre>" . print_r($this->getTree(), true) . "</pre>";
}
}
// Now, use the class with the givven data:
$categories = array(
array(
'id' => 1,
'category' => 'software',
'suboff' => 0
),
array(
'id' => 2,
'category' => 'programming',
'suboff' => 1
),
array(
'id' => 3,
'category' => 'Testing',
'suboff' => 1
),
array(
'id' => 4,
'category' => 'Designing',
'suboff' => 1
),
array(
'id' => 5,
'category' => 'Hospital',
'suboff' => 0
),
array(
'id' => 6,
'category' => 'Doctor',
'suboff' => 5
),
array(
'id' => 7,
'category' => 'Nurses',
'suboff' => 5
),
array(
'id' => 9,
'category' => 'Teaching',
'suboff' => 0
),
array(
'id' => 10,
'category' => 'php programming',
'suboff' => 2
),
array(
'id' => 11,
'category' => '.net programming',
'suboff' => 2
)
);
$myTree = new CategoryTree($categories);
echo $myTree;
?>
回答5:
This is what I just wrote for my app, and it works like a charm :)
$array = [
'i' => ['key' => 'i', 'name' => 'php programming', 'parent' => 'b'],
'g' => ['key' => 'g', 'name' => 'Nurses', 'parent' => 'e'],
'j' => ['key' => 'j', 'name' => '.net programming', 'parent' => 'b'],
'b' => ['key' => 'b', 'name' => 'programming', 'parent' => 'a'],
'a' => ['key' => 'a', 'name' => 'software', 'parent' => 'asd'],
'c' => ['key' => 'c', 'name' => 'Testing', 'parent' => 'a'],
'd' => ['key' => 'd', 'name' => 'Designing', 'parent' => 'a'],
'e' => ['key' => 'e', 'name' => 'Hospital', 'parent' => 'asd'],
'f' => ['key' => 'f', 'name' => 'Doctor', 'parent' => 'e'],
'h' => ['key' => 'h', 'name' => 'Teaching'],
];
function getAsTree(array &$array)
{
foreach ($array as $key => $item) {
if (isset($item['parent']) && isset($array[$item['parent']])) {
$array[$item['parent']]['children'][] = $item;
unset($array[$key]);
return getAsTree($array);
}
}
return $array;
}
And here is the result:
--- a: software ------ b: programming --------- i: php programming --------- j: .net programming ------ c: Testing ------ d: Designing --- e: Hospital ------ g: Nurses ------ f: Doctor --- h: Teaching
回答6:
IMHO the logic is:
- Get all the roots element (software, hospital and so on)
- Foreach root take the subelement(s) (for the software you'll take programming, testing and designing)
- Add the subelement(s) as subarray
- Loop recursively on the subarray(s) you just add
回答7:
You'll want to read the whole table into memory and turn it into a tree where each node can be identified with its corresponding id number. Then do a pre-order traversal of the tree to print it out.
回答8:
In PHP wenn i get the data from a Database:
"SELECT* FROM Table WHERE suboff LIKE 0"
foreach(item..)
"SELECT* FROM Table WHERE suboff LIKE item.ID"
foreach(item2..)
$result[item][item2]
回答9:
Here is a different approach that should be very easy to understand. It requires you to have the table ordered by suboff, i.e.
SELECT * FROM table ORDER BY suboff
Assuming the result is stored in $table, you can use this very concise php code:
// this will hold the result
$tree = array();
// used to find an entry using its id
$lookup = array();
foreach($table as $row){
if($row['suboff'] === 0){
// this has no parent, add it at base level
$tree[$row['category']] = array();
// store a reference
$lookup[$row['id']] =& $tree[$row['category']];
}else{
// find the right parent, add the category
$lookup[$row['suboff']][$row['category']] = array();
// store a reference
$lookup[$row['id']] =& $lookup[$row['suboff']][$row['category']];
}
}
回答10:
This solution works fine for me.
$array = array(
array('1','software','0'),
array('2','programming','1'),
array('3','Testing','1'),
array('4','Designing','1'),
array('5','Hospital','0'),
array('6','Doctor','5'),
array('7','Nurses','5'),
array('9','Teaching','0'),
array('10','php programming','2'),
array('11','.net programming','2')
);
$newArray = getTree($array);
function getTree( $rows, $suboff = 0) {
$return = array();
foreach($rows as $row) {
if($row[2] == $suboff){
$newrow = $row;
$subs = $this->getTree($rows, $row[0]);
if ( !empty($subs) ) {
$newrow['subs'] = $subs;
}
$return[] = $newrow;
}
}
return $return;
}
来源：https://stackoverflow.com/questions/7874849/how-to-sort-flat-array-into-multidimensional-tree