Question

我表格中的一栏有

之类的数据

category1_subcat_1
category1_subcat_2
category1_subcat_3
category2_subcat_1
category2_subcat_2
category3_subcat_1
category3_subcat_3

我想将其转换为嵌套数组，如

category1
 subcat1
 subcat2
 subcat3

category2
 subcat1
 subcat2

category3
 subcat1
 subcat3

我试过

foreach ($categories as $category){     

 $cat_array = explode("_",$category['cat_subcat']);
 $cat_subcat = array(
        'cat'=>$cat_array[0],
        'subcat'=>$cat_array[1]
        );
}

但如何按类别对此进行分组请帮助

Answer 1

试试这个..

<?php

$categories = [
    ['cat_subcat' => 'category1_subcat_1'],
    ['cat_subcat' => 'category1_subcat_2'],
    ['cat_subcat' => 'category1_subcat_3'],
    ['cat_subcat' => 'category2_subcat_1'],
    ['cat_subcat' => 'category2_subcat_2'],
    ['cat_subcat' => 'category3_subcat_1'],
    ['cat_subcat' => 'category3_subcat_3']
];

$finalCategories = [];

foreach ($categories as $category){
    $cat_array = explode("_",$category['cat_subcat']);
    $finalCategories[$cat_array[0]][] = $cat_array[1] . $cat_array[2];
}

echo "<pre>";
print_r($finalCategories);

输出将是......

Array
(
    [category1] => Array
        (
            [0] => subcat1
            [1] => subcat2
            [2] => subcat3
        )

    [category2] => Array
        (
            [0] => subcat1
            [1] => subcat2
        )

    [category3] => Array
        (
            [0] => subcat1
            [1] => subcat3
        )

)

添加以下代码行..

// Adding another loop
$output = [];
$i = 0;
foreach ($finalCategories as $category => $subCategories) {
    $output[$i]['cat_name'] = $category;
    foreach ($subCategories as $subCategory) {
        $output[$i]['sub_cat'][] = $subCategory;
    }
    $i++;
}

echo "<pre>";
print_r($output);

New Ouptut ..

Array
(
    [0] => Array
        (
            [cat_name] => category1
            [sub_cat] => Array
                (
                    [0] => subcat1
                    [1] => subcat2
                    [2] => subcat3
                )

        )

    [1] => Array
        (
            [cat_name] => category2
            [sub_cat] => Array
                (
                    [0] => subcat1
                    [1] => subcat2
                )

        )

    [2] => Array
        (
            [cat_name] => category3
            [sub_cat] => Array
                (
                    [0] => subcat1
                    [1] => subcat3
                )

        )

)

Answer 2

The Codez：

<?php

$str = <<<STR
category1_subcat_1
category1_subcat_2
category1_subcat_3
category2_subcat_1
category2_subcat_2
category3_subcat_1
category3_subcat_3
STR;

// Explode the string, with a newline as the delimiter
$lines = explode("\n", $str);
// Init the category array
$cats = [];
// iterate over the lines
foreach($lines as $currentLine) {
    // Match category{DIGIT} using regular exp
    preg_match("/category[0-9]/", $currentLine, $match);
    // Remove the $match from the current line
    $currentLine = str_replace($match[0], "", $currentLine);
    // Push the element to the categories array, and also remove the
    // the underscores (_)
    $cats[$match[0]][] = str_replace("_", "", $currentLine);
}
var_dump($cats);

输出：

array(3) {
  ["category1"]=>
  array(3) {
    [0]=>
    string(7) "subcat1"
    [1]=>
    string(7) "subcat2"
    [2]=>
    string(7) "subcat3"
  }
  ["category2"]=>
  array(2) {
    [0]=>
    string(7) "subcat1"
    [1]=>
    string(7) "subcat2"
  }
  ["category3"]=>
  array(2) {
    [0]=>
    string(7) "subcat1"
    [1]=>
    string(7) "subcat3"
  }
}

Working Example

Answer 3

因为OP要求嵌套数组而不是字典：

<?php

$nested_array = [];

foreach ($categories as $category){
  $exploded = explode("_",$category);
  if ($nested_array[-1,1] != $exploded[0]) {
    array_push($nested_array, $exploded[0])
  }
  array_push($nested_array[-1,1], $exploded[1].$exploded[2])
}

?>

缺少的部分实际上只是一个控制流程，用于在使用foreach遍历数组时检查是否已达到新类别。因此结果存储在$nested_array。

中

if ($nested_array[-1,1] != $exploded[0])正在检查$nested_array中存储的最后一个类别（最后一个元素）是否等于字符串的第一部分，如："category1" != "category1"或"category1" != "category2"等。

php嵌套数组爆炸

3 个答案:

The Codez：

输出：