Home >Backend Development >PHP Tutorial >PHP infinite classification best practices

PHP infinite classification best practices

高洛峰
高洛峰Original
2017-02-09 09:24:551079browse

Infinite Classification

  • is a very common and necessary function, almost every project has it.

  • Application scenarios: drop-down lists, tree lists, etc.

Types of infinite classification

  • Front-end implementation (The front-end framework has generally been implemented, and it can be generated as long as the back-end transmits data to the front-end in the specified format)

  • Back-end Implementation(The following mainly talks about this kind of implementation)

Infinitely multiple implementations

  • The first type (recommended)

function infiniteSort($data, $showFName, $titleFName, $pidFName = 'pid', $idFName = 'id', $levelFName = 'level', $pid = 0, $level = 0)
{
    $tree = array();

    foreach ($data as $key => $value) {

        if ($value[$pidFName] == $pid) {
            $value[$levelFName] = $level;
            $value[$showFName] = str_repeat('  ', $level) . '|-' . $value[$titleFName];
            $tree[] = $value;
            unset($data[$key]);
            $tempArr = infiniteSort($data, $showFName, $titleFName, $pidFName, $idFName, $level, $value[$idFName], $level + 1);
            if(!empty($tempArr)){
                $tree = array_merge($tree, $tempArr);
            }
        }

    }

    return $tree;
}

Note:
1, $data All data that has been sorted by asc
2, $showFName Display name Field name of the title (formatted)
3. $titleFName Field name of the title (unformatted)
4. $levelFName Level field name
5, $pidFName The field name of the parent id
6, $idFName The field name of the id

  • The second type (using reference variables)

/**
 * 无限级分类
 * @param Array $treeList //接受处理完成数据的数组
 * @param Array $data //数据库里获取的结果集
 * @param String $level //格式化层级字段名
 * @param Int $pid
 * @param Int $count //第几级分类
 */
function tree(&$treeList, &$data, $level, $show_name, $field_name, $field_pid = 'pid', $field_id = 'id', $pid = 0, $count = 0)
{
    foreach ($data as $key => $value) {

        if ($value[$field_pid] == $pid) {
            $value[$level] = $count;
            $value[$show_name] = str_repeat('    ',$count).'|-'.$value[$field_name];
            $treeList[] = $value;
            unset($data[$key]);
            tree($treeList, $data, $level, $show_name, $field_name,$field_pid, $field_id, $value[$field_id], $count+1);
        }

    }
}

Note:
1, $data All data that has been sorted by asc
2 , the returned infinite list data is stored in $treeList

  • The third type (there are restrictions on using static variables: if a request is called twice to achieve 2 Infinite level classification will cause problems, so it is not recommended)

    public function getTree($list, $parent_id, $level=0) {
        //应该是静态的局部变量,这样才能保证,在递归调用时,所有
        //的getTree方法,操作的是一个Tree空间。
        static $tree = array();//保存找到的分类的数组
        //遍历所有分类,通过parent_id判断,哪些是我们正在查找的
        foreach($list as $row) {
            //判断当前所遍历的分类$row, 是否是当前需要查找的子分类
            if($row['pid'] == $parent_id) {
                //找到了一个分类
                //存起来,存哪?
                $row['level'] = $level;
                $tree[] = $row;
                //继续查找当前$row所代表的分类的子分类
                $this->getTree($list, $row['id'], $level+1);
            }
        }
        return $tree;
    }

Note:
1, $list All data that has been sorted by asc

Unlimited classification

  • is a very common and necessary function, almost every project has it.

  • Application scenarios: drop-down lists, tree lists, etc.

Types of infinite classification

  • Front-end implementation (The front-end framework has generally been implemented, and it can be generated as long as the back-end transmits data to the front-end in the specified format)

  • Back-end Implementation(The following mainly talks about this kind of implementation)

Infinitely multiple implementations

  • The first type (recommended)

function infiniteSort($data, $showFName, $titleFName, $pidFName = 'pid', $idFName = 'id', $levelFName = 'level', $pid = 0, $level = 0)
{
    $tree = array();

    foreach ($data as $key => $value) {

        if ($value[$pidFName] == $pid) {
            $value[$levelFName] = $level;
            $value[$showFName] = str_repeat('  ', $level) . '|-' . $value[$titleFName];
            $tree[] = $value;
            unset($data[$key]);
            $tempArr = infiniteSort($data, $showFName, $titleFName, $pidFName, $idFName, $level, $value[$idFName], $level + 1);
            if(!empty($tempArr)){
                $tree = array_merge($tree, $tempArr);
            }
        }

    }

    return $tree;
}

Note:
1, $data All data that has been sorted by asc
2,$ showFName Display the field name of the name (formatted)
3, $titleFName The field name of the title (unformatted)
4, $levelFName Hierarchical field name
5, $pidFName Field name of parent id
6, $idFName Field name of id

  • Second type (using reference variables)

/**
 * 无限级分类
 * @param Array $treeList //接受处理完成数据的数组
 * @param Array $data //数据库里获取的结果集
 * @param String $level //格式化层级字段名
 * @param Int $pid
 * @param Int $count //第几级分类
 */
function tree(&$treeList, &$data, $level, $show_name, $field_name, $field_pid = 'pid', $field_id = 'id', $pid = 0, $count = 0)
{
    foreach ($data as $key => $value) {

        if ($value[$field_pid] == $pid) {
            $value[$level] = $count;
            $value[$show_name] = str_repeat('    ',$count).'|-'.$value[$field_name];
            $treeList[] = $value;
            unset($data[$key]);
            tree($treeList, $data, $level, $show_name, $field_name,$field_pid, $field_id, $value[$field_id], $count+1);
        }

    }
}

Note:
1, $data All data that has been sorted by asc
2. The returned infinite-level list data is stored in $treeList

  • The third type (there are restrictions on using static variables: if one request calls Implementing two infinite levels of classification twice will cause problems, so it is not recommended)

    public function getTree($list, $parent_id, $level=0) {
        //应该是静态的局部变量,这样才能保证,在递归调用时,所有
        //的getTree方法,操作的是一个Tree空间。
        static $tree = array();//保存找到的分类的数组
        //遍历所有分类,通过parent_id判断,哪些是我们正在查找的
        foreach($list as $row) {
            //判断当前所遍历的分类$row, 是否是当前需要查找的子分类
            if($row['pid'] == $parent_id) {
                //找到了一个分类
                //存起来,存哪?
                $row['level'] = $level;
                $tree[] = $row;
                //继续查找当前$row所代表的分类的子分类
                $this->getTree($list, $row['id'], $level+1);
            }
        }
        return $tree;
    }

Note:
1, $list All data that has been sorted by asc

For more articles related to PHP infinite classification best practices, please pay attention to the PHP Chinese website!

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn