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PHP MySQL method to implement unlimited classification columns, _PHP tutorial
PHP MySQL method to implement unlimited classification columns, _PHP tutorial
How to implement unlimited classification columns with PHP MySQL,
This article describes the method of implementing unlimited classification columns with PHP MySQL. Share it with everyone for your reference, the details are as follows:
A very simple, clear and simple unlimited classification example with indentation effect. You only need to query the data table once and then recursively traverse the result set. If you want to implement column indentation display in PHP, you can refer to it.
$sql = 'select * from cat order by cat_id desc';
$list = $db->getAll($sql);
$list = getLevelCat($list);
function getLevelCat($catlist, $parent_id='0', $html=' ', $level='0'){
$arr = array();
foreach($catlist as $val){
if($val['parent_id']==$parent_id){
$val['html'] = str_repeat($html,$level);
$val['level'] = $level;
$arr[] = $val;
$arr = array_merge($arr, getLevelCat($catlist, $val['cat_id'], $html, $level+1));
}
}
return $arr;
}
Implementation renderings:
Just a few lines of code, clearer and easier to use.
I hope this article will be helpful to everyone in PHP programming.
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