PHP Recursive algorithm php recursive function infinite class classification

< /** * Function: Query all categories to generate tree menu * @param int $pid Parent ID start Query from top level by default */ function Totree ($pid =0) { Query all top-level categories Database connections There's not much to say here. $model =m (' Category '); instantiation model Query Map criteria $map =array ( ' pid ' = $pid, ); Inquire $data = $model->where ($map)->select (); Defines a new array to store the generated HTML tree menu $html _array=array (); Cycle classification $html = "; $padding = 0; Indent in foreach ($data as $k = = $v) { Indent based on the value of the path field $path = $v [' path ']; if ($path &&strpos ($v [' Path '], '-')) { $path _array= @explode ('-', $v [' path ']); $count =count ($path _array)-1; $padding = $count *20; Next level classification indent 20 pixels } Current categorical data HTML $data _array[]= ' '. $v [' name ']. ' '; Recursively start looking up sub-categories $data _array[]=totree ($v [' id ']);//recursively recursive the ID of the current classification as the parent ID } foreach Loop ends Merge categorical HTML array $html. =implode (", $data _array ()); $html. = '; HTML Tree Menu Construction is complete, so simple, so easy! return $html; } Copy Code

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