fastadmin 自带 Tree 类生成树型结构，该类所在位置extend/fast/Tree.php

获取实例

$tree = Tree::instance();

初始化

$data = [
    ['id' => 1, 'pid' => 0, 'name' => '一级分类'],
    ['id' => 2, 'pid' => 1, 'name' => '二级分类'],
    ['id' => 3, 'pid' => 2, 'name' => '三级分类'],
];
   /**
     * 初始化方法
     * @param array  $arr     2维数组，例如：
     *      array(
     *      1 => array('id'=>'1','pid'=>0,'name'=>'一级栏目一'),
     *      2 => array('id'=>'2','pid'=>0,'name'=>'一级栏目二'),
     *      3 => array('id'=>'3','pid'=>1,'name'=>'二级栏目一'),
     *      4 => array('id'=>'4','pid'=>1,'name'=>'二级栏目二'),
     *      5 => array('id'=>'5','pid'=>2,'name'=>'二级栏目三'),
     *      6 => array('id'=>'6','pid'=>3,'name'=>'三级栏目一'),
     *      7 => array('id'=>'7','pid'=>3,'name'=>'三级栏目二')
     *      )
     * @param string $pidname 父字段名称
     * @param string $nbsp    空格占位符
     * @return Tree
     */
$tree->init($data, 'pid', '#');

获取树状数组

/**
 *
 * 获取树状数组
 * @param string $myid       要查询的ID
 * @param string $itemprefix 前缀
 * @return array
 */
$treeArr = $tree->getTreeArray(0, '$');
// 结果返回, 如果前缀和占位符都不穿,spacer为空字符串
/*
array(1) {
  [0] => array(5) {
    ["id"] => int(1)
    ["pid"] => int(0)
    ["name"] => string(12) "一级分类"
    ["spacer"] => string(4) "$└"
    ["childlist"] => array(1) {
      [0] => array(5) {
        ["id"] => int(2)
        ["pid"] => int(1)
        ["name"] => string(12) "二级分类"
        ["spacer"] => string(6) "$##└"
        ["childlist"] => array(1) {
          [0] => array(5) {
            ["id"] => int(3)
            ["pid"] => int(2)
            ["name"] => string(12) "三级分类"
            ["spacer"] => string(8) "$####└"
            ["childlist"] => array(0) {
            }
          }
        }
      }
    }
  }
}
*/

将getTreeArray的结果返回为二维数组

/**
 * 将getTreeArray的结果返回为二维数组
 * @param array  $data
 * @param string $field
 * @return array
 */
$list = $tree->getTreeList($treeArr, 'name')
// 返回结果
/*
array(3) {
  [0] => array(5) {
    ["id"] => int(1)
    ["pid"] => int(0)
    ["name"] => string(17) "$└ 一级分类"
    ["spacer"] => string(4) "$└"
    ["haschild"] => int(1)
  }
  [1] => array(5) {
    ["id"] => int(2)
    ["pid"] => int(1)
    ["name"] => string(19) "$##└ 二级分类"
    ["spacer"] => string(6) "$##└"
    ["haschild"] => int(1)
  }
  [2] => array(5) {
    ["id"] => int(3)
    ["pid"] => int(2)
    ["name"] => string(21) "$####└ 三级分类"
    ["spacer"] => string(8) "$####└"
    ["haschild"] => int(0)
  }
}
*/