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HomeBackend DevelopmentPHP Tutorial 发布两个不用递归的树形数组构造函数,该如何处理

发布两个不用递归的树形数组构造函数
发布两个不用递归的树形数组构造函数

PHP code
<!--

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-->/**
 * 创建父节点树形数组
 * 参数
 * $ar 数组,邻接列表方式组织的数据
 * $id 数组中作为主键的下标或关联键名
 * $pid 数组中作为父键的下标或关联键名
 * 返回 多维数组
 **/
function find_parent($ar, $id='id', $pid='pid') { 
  foreach($ar as $v) $t[$v[$id]] = $v;
  foreach ($t as $k => $item){
    if( $item[$pid] ){
      if( ! isset($t[$item[$pid]]['parent'][$item[$pid]]) )
         $t[$item[$id]]['parent'][$item[$pid]] =& $t[$item[$pid]];
    }
  } 
  return $t;
}


/**
 * 创建子节点树形数组
 * 参数
 * $ar 数组,邻接列表方式组织的数据
 * $id 数组中作为主键的下标或关联键名
 * $pid 数组中作为父键的下标或关联键名
 * 返回 多维数组
 **/
function find_child($ar, $id='id', $pid='pid') {
  foreach($ar as $v) $t[$v[$id]] = $v;
  foreach ($t as $k => $item){
    if( $item[$pid] ) {
      $t[$item[$pid]]['child'][$item[$id]] =& $t[$k];
    }
  }
  return $t;
}

示例
PHP code
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-->$data = array(
  array('ID'=>1, 'PARENT'=>0, 'NAME'=>'祖父'),
  array('ID'=>2, 'PARENT'=>1, 'NAME'=>'父亲'),
  array('ID'=>3, 'PARENT'=>1, 'NAME'=>'叔伯'),
  array('ID'=>4, 'PARENT'=>2, 'NAME'=>'自己'),
  array('ID'=>5, 'PARENT'=>4, 'NAME'=>'儿子'),
);

$p = find_parent($data, 'ID', 'PARENT');
$c = find_child($data, 'ID', 'PARENT');




------解决方案--------------------
谢谢分享。
------解决方案--------------------
版主辛苦了,多谢分享
------解决方案--------------------
谢谢版主。。学习了。。
------解决方案--------------------
版主的示例写错了一点点 $data;
------解决方案--------------------
数据结构中的ID去掉岂不是更好 不仅少一次循环 还从语法层面拒绝了ID重复的可能

PHP code

function find_child($ar, $pid='pid') {
    foreach ($ar as $k => $item){
        if( $item[$pid] ) {
            $ar[$item[$pid]]['child'][$k] = &$ar[$k];
        }
    }
    return $ar;
}


function find_parent($ar,$pid='pid') { 
    foreach ($ar as $k => $item){
        if( $item[$pid] ){
            if( ! isset($ar[$item[$pid]]['parent'][$item[$pid]]) )
                $ar[$k]['parent'][$item[$pid]] =& $ar[$item[$pid]];
        }
    }
    return $ar;
}
<br><font color="#e78608">------解决方案--------------------</font><br>前排就座,参观学习
<br><font color="#e78608">------解决方案--------------------</font><br>
这两个函数对数组的顺序有要求:<br><br>可以试一下:<br>$data = array(<br> array('ID'=>5, 'PARENT'=>4, 'NAME'=>'d'),<br> array('ID'=>1, 'PARENT'=>0, 'NAME'=>'x'),<br> array('ID'=>2, 'PARENT'=>1, 'NAME'=>'y'),<br> array('ID'=>3, 'PARENT'=>1, 'NAME'=>'z'),<br> array('ID'=>4, 'PARENT'=>2, 'NAME'=>'c'),<br>);<br><br>或者:<br>$data = array(<br> array('ID'=>1, 'PARENT'=>0, 'NAME'=>'a'),<br> array('ID'=>2, 'PARENT'=>1, 'NAME'=>'b'),<br> array('ID'=>3, 'PARENT'=>5, 'NAME'=>'c'),<br> array('ID'=>4, 'PARENT'=>2, 'NAME'=>'d'),<br> array('ID'=>5, 'PARENT'=>1, 'NAME'=>'e'),<br>);<br><br><br>$data = array(<br> array('ID'=>1, 'PARENT'=>0, 'NAME'=>'1'),<br> array('ID'=>2, 'PARENT'=>1, 'NAME'=>'11'),<br> array('ID'=>3, 'PARENT'=>5, 'NAME'=>'12'),<br> array('ID'=>4, 'PARENT'=>2, 'NAME'=>'111'),<br> array('ID'=>5, 'PARENT'=>1, 'NAME'=>'1111'),<br>);
<br><font color="#e78608">------解决方案--------------------</font><br>
,,奥妙在于 &<br><br>注意函数名find_parent, find_child,并非构造整个上下级树
<br><font color="#e78608">------解决方案-------------------- <div class="clear">
                 
              
              
        
            </div></font>
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