Unlimited classification implemented by recursion in php

Unlimited classification implemented by recursion in php Header ("Content-type: text/html; charset = utf-8 ");
/**
*
* @ Category contry_category: implements an unlimited classification. similar categories are commonly used in topic navigation.
*
*/


/**
+ ------------------------------------------------------------------------------- +
| Id name Category id |
| 1 China 0 |
| 2 Beijing 1 |
| 3 Shanghai 1 |
| 4 US 0 |
* 5 New York 4 *
* 6 Washington 4 *
* 7 Virginia 4 *
+ ------------------------------------------------------------------------------- +
*
* Top-level columns whose Category id is 0
* If the category id is the same as the id, the corresponding category is used.
*/


Class contry_category {
Public $ I =-1;
Public function index ($ array ){
$ This-> I ++;
If ($ array [$ this-> I] ['Category _ id'] = 0 ){
Echo "success". $ array [$ this-> I] ["name"]."
";
For ($ j = 0; $ j <count ($ array); $ j ++ ){
If ($ array [$ j] ['Category _ id'] = $ array [$ this-> I] ['id']) {// view the category
Echo "audio-extract". $ array [$ j] ["name"]."
";
}
}
}
Foreach ($ array as $ v ){
If ($ v ['Category _ id'] = 0)
$ Ary [] = $ v ['Category _ id']; // Obtain several top-level columns to determine the number of recursion times.
}

If ($ this-> I <= count ($ ary ))
$ This-> index ($ array); // recursion
}
}
$ Infos = array ("id" => 1, 'name' => "China", "category_id" => 0), array ("id" => 2, 'name' => "Beijing", "category_id" => 1), array ("id" => 3, 'name' => "Shanghai ", "category_id" => 1), array ("id" => 4, 'name' => "us", "category_id" => 0 ), array ("id" => 5, 'name' => "New York", "category_id" => 4), array ("id" => 6, 'name' => "Washington", "category_id" => 4), array ("id" => 7, 'name' => "Virginia, California ", "category_id" => 4 ));

$ Obj = new contry_category ();
$ Obj-> index ($ infos );






/**
* The printed result is as follows:
* Shanghai China
BEIJING-Beijing
─ ── Shanghai
United States
├ ── New York
WASHINGTON-Washington
California-Virginia
*/