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html - PHP reads classification and generates two-dimensional array. Two-dimensional array values are repeated.
- WBOYOriginal
- 2016-09-11 11:34:121062browse
Read the category directory to generate a two-dimensional array under the top category that contains other categories under the top level
But the two-dimensional array under the next top-level category directory will contain the value of the previous top-level directory. It seems to be the reason for static declaration of variables, but I don’t know how. It’s the same after changing the release. Below is a screenshot to ask for a reason:
Picture description
Reply content:
Read the category directory to generate a two-dimensional array under the top category that contains other categories under the top level
But the two-dimensional array under the next top-level category directory will contain the value of the previous top-level directory. It seems to be the reason for static declaration of variables, but I don’t know how. It’s the same after changing the release. Below is a screenshot to ask for a reason:
Picture description
I searched again and the following one should meet the requirements.
<code><?php
$arr= array(
'1'=>array('id'=>1, 'pid'=>0,),
'2'=>array('id'=>2, 'pid'=>0,),
'3'=>array('id'=>3, 'pid'=>1,),
'4'=>array('id'=>4, 'pid'=>2,),
'5'=>array('id'=>5, 'pid'=>4),
'6'=>array('id'=>6, 'pid'=>5,),
'7'=>array('id'=>7, 'pid'=>3),
'8'=>array('id'=>8, 'pid'=>4,),
'9'=>array('id'=>9, 'pid'=>7),
);
//以ID为键值格式化
foreach ($arr as $key => $value) {
$list[$value['id']]=$value;
}
//遍历数组
foreach ($list as $key => $value) {
if($value['pid']==0){
$tree[$value['id']]=$value;
}else{
//祖先ID
$ancestor_id='';
//判断祖先数组里面有没有对应的值，有则取出
if(!empty($ancestor[$value['pid']])){
$ancestor_id=$ancestor[$value['pid']];
}else{
$topid=$value['id'];
$child=array();
if(empty($ancestor[$topid])){
$child[]=$topid;
}
//通过循环，一层一层的往上找，找出他们各自的父亲，直到祖宗为止
while($list[$topid]['pid'] > 0)
{
$topid = $list[$topid]['pid'];
if(empty($topid)){
$topid='';
break;
}else{
//祖宗数组里面没有，则放入子孙数组
if(empty($ancestor[$topid])){
$child[]=$topid;
}else{
//祖先已经存在，就不用循环下去了
$topid=$ancestor[$topid];
break;
}
}
}
$ancestor_id= $topid;
//如果找到祖宗，就将子孙数组对应加入到祖宗数组里面
if(!empty($ancestor_id)){
foreach ($child as $k => $v) {
$ancestor[$v]=$ancestor_id;
}
}
}
if(!empty($ancestor_id)){
$tree[$ancestor_id]['child'][$value['id']]=$value;
}
}
}
echo '<pre class="brush:php;toolbar:false">';
var_dump($tree);
</code>