1.循环迭代实现无限极分类
public function test(){
// 数组下标与id 一致
$depart_list = [
1 => ['id' => 1, 'grp_name' => '技术部', 'pid' => 0],
2 => ['id' => 2, 'grp_name' => '业务中台', 'pid' => 1],
3 => ['id' => 3, 'grp_name' => '业务前台', 'pid' => 1],
4 => ['id' => 4, 'grp_name' => '业务后台', 'pid' => 1],
5 => ['id' => 5, 'grp_name' => '客服组', 'pid' => 2],
6 => ['id' => 6, 'grp_name' => '管理系统组', 'pid' => 2],
7 => ['id' => 7, 'grp_name' => '支付组', 'pid' => 2],
8 => ['id' => 8, 'grp_name' => '用户组', 'pid' => 4],
9 => ['id' => 9, 'grp_name' => '司机组', 'pid' => 4],
10 => ['id' => 10, 'grp_name' => 'ios组', 'pid' => 3],
11 => ['id' => 11, 'grp_name' => 'android组', 'pid' => 3],
];
$depart_data = $this->generateTree($depart_list);
print_r(json_encode($depart_data, JSON_UNESCAPED_UNICODE));
}
function generateTree($items){
$tree = array();
foreach($items as $item){
if(isset($items[$item['pid']])){
$items[$item['pid']]['son'][] = &$items[$item['id']];
}else{
$tree[] = &$items[$item['id']];
}
}
return $tree;
}
输出结果如下：
[
{
"id": 1,
"grp_name": "技术部",
"pid": 0,
"son": [
{
"id": 2,
"grp_name": "业务中台",
"pid": 1,
"son": [
{
"id": 5,
"grp_name": "客服组",
"pid": 2
},
{
"id": 6,
"grp_name": "管理系统组",
"pid": 2
},
{
"id": 7,
"grp_name": "支付组",
"pid": 2
}
]
},
{
"id": 3,
"grp_name": "业务前台",
"pid": 1,
"son": [
{
"id": 10,
"grp_name": "ios组",
"pid": 3
},
{
"id": 11,
"grp_name": "android组",
"pid": 3
}
]
},
{
"id": 4,
"grp_name": "业务后台",
"pid": 1,
"son": [
{
"id": 8,
"grp_name": "用户组",
"pid": 4
},
{
"id": 9,
"grp_name": "司机组",
"pid": 4
}
]
}
]
}
]
分析:
这个算法利用了循环迭代,将线性结构按照父子关系以树形结构输出,算法的关键在于使用了引用.
优点:速度快,效率高.
缺点:数组的key值必须与id值相同,不便于取出数据(同样使用迭代获取数据)
2.递归实现无限极分类:
public function test(){
$depart_list = [
// 数组下标与id 可以不一致
0 => ['id' => 1, 'grp_name' => '技术部', 'pid' => 0],
1 => ['id' => 2, 'grp_name' => '业务中台', 'pid' => 1],
2 => ['id' => 3, 'grp_name' => '业务前台', 'pid' => 1],
3 => ['id' => 4, 'grp_name' => '业务后台', 'pid' => 1],
4 => ['id' => 5, 'grp_name' => '客服组', 'pid' => 2],
5 => ['id' => 6, 'grp_name' => '管理系统组', 'pid' => 2],
6 => ['id' => 7, 'grp_name' => '支付组', 'pid' => 2],
7 => ['id' => 8, 'grp_name' => '用户组', 'pid' => 4],
8 => ['id' => 9, 'grp_name' => '司机组', 'pid' => 4],
9 => ['id' => 10, 'grp_name' => 'ios组', 'pid' => 3],
10 => ['id' => 11, 'grp_name' => 'android组', 'pid' => 3],
];
$depart_data = $this->generateTree($depart_list, 0, 0);
foreach ($depart_data as $val){
echo $val['grp_name'].'
';
}
}
public function generateTree(array $items, $id, $step){
static $tree=[];
foreach($items as $key=>$val) {
if($val['pid'] == $id) {
$flg = str_repeat('―',$step*2);
$val['grp_name'] = $flg.$val['grp_name'];
$tree[] = $val;
$this->generateTree($items , $val['id'] ,$step+1);
}
}
return $tree;
}
输出如下：
BFC397D8-2535-4C62-9708-9BA121941774.png
分析:
利用了递归,数组的key值与id值可以不相同,最后以顺序的结构输出数组
优点:方便遍历,查找父子元素
缺点:php不擅长递归,数据量大的情况下效率会显著降低
