php - 值未分配给变量

Question

我有一个类别数组，其中 id 是类别的 id，parent 表示类别的父 id(id 0 表示最顶部的父节点)，value 是数组的标题。路径最初设置为类别的 id。数组如下:

Array
(
    [0] => Array
        (
            [id] => 1
            [parent] => 0
            [value] => Corporate Files
            [path] => 1
        )

    [1] => Array
        (
            [id] => 2
            [parent] => 0
            [value] => Products Files
            [path] => 2
        )

    [2] => Array
        (
            [id] => 3
            [parent] => 1
            [value] => Communications Materials
            [path] => 3
        )

    [3] => Array
        (
            [id] => 4
            [parent] => 1
            [value] => Group Technical
            [path] => 4
        )

    [4] => Array
        (
            [id] => 5
            [parent] => 1
            [value] => New Projects
            [path] => 5
        )

    [5] => Array
        (
            [id] => 6
            [parent] => 2
            [value] => Product Range
            [path] => 6
        )

    [6] => Array
        (
            [id] => 7
            [parent] => 2
            [value] => WL4
            [path] => 7
        )
);

我想在数组中生成类别的路径。所以输出应该是

Array
(
    [0] => Array
        (
            [id] => 1
            [parent] => 0
            [value] => Corporate Files
            [path] => 1
        )

    [1] => Array
        (
            [id] => 2
            [parent] => 0
            [value] => Products Files
            [path] => 2
        )

    [2] => Array
        (
            [id] => 3
            [parent] => 1
            [value] => Communications Materials
            [path] => 1,3
        )

    [3] => Array
        (
            [id] => 4
            [parent] => 1
            [value] => Group Technical
            [path] => 1,4
        )

    [4] => Array
        (
            [id] => 5
            [parent] => 1
            [value] => New Projects
            [path] => 1,5
        )

    [5] => Array
        (
            [id] => 6
            [parent] => 2
            [value] => Product Range
            [path] => 2,6
        )

    [6] => Array
        (
            [id] => 7
            [parent] => 2
            [value] => WL4
            [path] => 2,7
        )
);

我写了以下函数。

   function findparent($id,$path){
        global $categories;
        global $catcnt;

        if($id==0){
            echo $path."<br />"; //this outputs path currently
            return $path;
        }
        for($i=0;$i<$catcnt;$i++){

            if($id==$categories[$i]['id']){
                $path=$id.",".$path;
                findparent($categories[$i]['parent'],$path);
            }
        }
    }

for($i=0;$i<count($categories);$i++){
             $categories[$i]['path']=(string)findparent($categories[$i]['parent'],$categories[$i]['id']); //this doesnt assign it currectly

    }

输出是:

Array
(
    [0] => Array
        (
            [id] => 1
            [parent] => 0
            [value] => Corporate Files
            [path] => 
        )

    [1] => Array
        (
            [id] => 2
            [parent] => 0
            [value] => Products Files
            [path] => 
        )

    [2] => Array
        (
            [id] => 3
            [parent] => 1
            [value] => Communications Materials
            [path] => 
        )

    [3] => Array
        (
            [id] => 4
            [parent] => 1
            [value] => Group Technical
            [path] => 
        )

    [4] => Array
        (
            [id] => 5
            [parent] => 1
            [value] => New Projects
            [path] => 
        )

    [5] => Array
        (
            [id] => 6
            [parent] => 2
            [value] => Product Range
            [path] => 
        )

    [6] => Array
        (
            [id] => 7
            [parent] => 2
            [value] => WL4
            [path] => 
        )
);

我哪里错了？

Answer 1

findparent仅在 id 时返回为零。

在递归 findparent 之前，您需要第二个 return 语句。称呼。