父子關係的船最多n個子

Question

我有SQL結構

id parent_id 
1  0 
2  1 
3  2 
4  3 
5  4 
6  5 
7  1 
8  7 
9  8 

我想要使用呼叫ID的所有子子= 1到n個子節點PHP

我怎樣才能得到它。我是通過使用PHP回調函數結構。

Answer 1

通過使用遞歸你可以...

<?php 
$arrayParent = $this->ToDatabase->("SELECT * FROM table WHERE parent_id = 0"); 
BuildList($arrayParent, 0); 

function BuildList($arrayElements, $depth) 
{ 
    foreach($arrayElements as $element) 
    { 
     echo str_repeat("&nbsp;&nbsp;", $depth) . $element["id"]; 
     $depth++; 
     $totalUnder = $this->ToDatabase->("SELECT * FROM table 
         WHERE parent_id = " . (int)$element["id"]); 
     if(count($totalUnder) > 0) 
      $depth = BuildList($totalUnder, $depth); //$totalUnder fetch to array and step deeper... 

     return $depth; 
    } 
} 
?>