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
-software
--programming
---php programming
--- .net programming
--testing
--designing
-hospital
--doctor
--nurses
-teaching
假设您的数据库引擎是MySQL：
// 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);
像这样的工作，请使用引用。
$array = array(
array('1','software','0'),
array('2','programming','1'),
array('3','Testing','1'),
array('4','Designing','1'),
array('5','Hospital','0'),
array('6','Doctor','5'),
array('7','Nurses','5'),
array('9','Teaching','0'),
array('10','php programming','2'),
array('11','.net programming','2')
);
function menu_sort($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);
结果...
software
programming
php programming
.net programming
Testing
Designing
Hospital
Doctor
Nurses
Teaching
<ul />。 - middus这个类将一个扁平的分类数组转换成一个结构化的树形数组：
<?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 $myTree;
?>
首先，您需要解析此表。我假设您可以自己完成；如果不行，请搜索“正则表达式”，它们是您的朋友。
您正在使用的数据结构是经典的树。您将需要两个数组来处理它。第一个是节点数组$nodes，其中键是节点ID，值是节点名称，第二个是链接数组$links，其中每个键是父节点，每个值是子节点的数组（对于每个元素，$links[$id][] = $suboff就足够了）。
现在，您必须递归地遍历您拥有的树。您可以引入一个函数，其签名如下：
function print_node( $nodeID, $level = 1 )
此函数应打印节点本身（存储在$nodes中的信息），并使用$level填充破折号调用自身以呈现所有子节点。它们将依次呈现所有子节点的子节点等。您只需为顶级节点调用此函数即可。
$array = [
'i' => ['key' => 'i', 'name' => 'php programming', 'parent' => 'b'],
'g' => ['key' => 'g', 'name' => 'Nurses', 'parent' => 'e'],
'j' => ['key' => 'j', 'name' => '.net programming', 'parent' => 'b'],
'b' => ['key' => 'b', 'name' => 'programming', 'parent' => 'a'],
'a' => ['key' => 'a', 'name' => 'software', 'parent' => 'asd'],
'c' => ['key' => 'c', 'name' => 'Testing', 'parent' => 'a'],
'd' => ['key' => 'd', 'name' => 'Designing', 'parent' => 'a'],
'e' => ['key' => 'e', 'name' => 'Hospital', 'parent' => 'asd'],
'f' => ['key' => 'f', 'name' => 'Doctor', 'parent' => 'e'],
'h' => ['key' => 'h', 'name' => 'Teaching'],
];
function getAsTree(array &$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;
}
这里是结果：
--- a: software
------ b: programming
--------- i: php programming
--------- j: .net programming
------ c: Testing
------ d: Designing
--- e: Hospital
------ g: Nurses
------ f: Doctor
--- h: Teaching
在 PHP 中，当我从数据库获取数据时：
"SELECT* FROM Table WHERE suboff LIKE 0"
foreach(item..)
"SELECT* FROM Table WHERE suboff LIKE item.ID"
foreach(item2..)
$result[item][item2]
这里有一个不同的方法，应该非常容易理解。它要求您按suboff排序表格，即
SELECT * FROM table ORDER BY suboff
$table中，您可以使用这个非常简洁的PHP代码：// 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']];
}
}
这个解决方案对我来说很好用。
$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;
}
我认为逻辑是这样的：