PHP 读取带有模式的 txt 文件并保留信息

Question

抱歉，标题令人困惑，但我想不出另一个。

我有一个这种格式的文本文件(只是断章取义的几行):

# Google_Product_Taxonomy_Version: 2015-02-19
1 - Animals & Pet Supplies
3237 - Animals & Pet Supplies > Live Animals
2 - Animals & Pet Supplies > Pet Supplies
3 - Animals & Pet Supplies > Pet Supplies > Bird Supplies
7385 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cage Accessories
499954 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cage Accessories > Bird Cage Bird Baths
7386 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cage Accessories > Bird Cage Food & Water Dishes
4989 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cages & Stands
4990 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Food

到目前为止，还不错。我想编写一个解析器，其中包含每个类别的所有信息。工作完成后，它必须写在一个mysql-DB中。

正好有:

1 unique ID
1 Main-category 
n sub-categories

棘手的部分(对我而言)是如何保留这些信息并将它们保存在一个数组中，这与性能有关。

我的数据库必须有这样的最终输出

ID    | parent | title | 
1     |        | Animals & Pet Supplies
3232  |   1    | Live Animals
2     |   1    | Pet Supplies
3     |   2    | Bird Supplies

事实上，我必须能够通过我的 DB 条目重现这个“面包屑”。

我的解析器是这样开始的:

public function enrichTaxonomy()
{
    $aOutput = array();

    // ignore first line
    fgets($handle);

    // iterate throug it
    while (($line = fgets($handle)) !== false)
    {
        $splitted = explode("-", $line);

        // build first level
        if (strpos($splitted[1], '>') === false)
        {
            $aOutput['id'][] = trim($splitted[0]);
            $aOutput['title'][] = trim($splitted[1]);
        } else
        {
            // recursive?
            if (substr_count($splitted[1], " > ") == 1)
            {
                $splitted2ndLevel = explode(" > ", $splitted[1]);
                $aOutput['id'][] = trim($splitted[0]);
                $aOutput['title'][] = trim($splitted2ndLevel[1]);
            }
        }
    }

    echo "<pre>";
    var_dump($aOutput);
    echo "</pre>";
}

但我意识到，这不是一个很好的方法，因为我的下一步应该是:

if (substr_count($splitted[1], " > ") == 2)
{
    $splitted3rdLevel = explode(" > ", $splitted[1]);
    $aOutput['id'][] = trim($splitted[0]);
    $aOutput['title'][] = trim($splitted3rdLevel[2]);
}

if (substr_count($splitted[1], " > ") == 3)
{
    $splitted4thLevel = explode(" > ", $splitted[1]);
    $aOutput['id'][] = trim($splitted[0]);
    $aOutput['title'][] = trim($splitted4thLevel[3]);
}

此外，这似乎在之后变得非常复杂，当我尝试拥有一个最终数组时，我可能会迭代该数组以将此数据插入我的数据库中。

重要的一点是，每个“子类别”都必须知道它的“父亲”，所以我也可以插入“父”-id。

我现在的问题:什么是实现此目标的良好、简短(相对)、高效的方法？

Answer 1

当您需要再次展平它以插入数据库时​​，无需构建树结构，而是创建与数据库相同的结构:

$input = <<<'EOD'
1 - Animals & Pet Supplies
3237 - Animals & Pet Supplies > Live Animals
2 - Animals & Pet Supplies > Pet Supplies
3 - Animals & Pet Supplies > Pet Supplies > Bird Supplies
7385 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cage Accessories
499954 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cage Accessories > Bird Cage Bird Baths
7386 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cage Accessories > Bird Cage Food & Water Dishes
4989 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Cages & Stands
4990 - Animals & Pet Supplies > Pet Supplies > Bird Supplies > Bird Food
EOD;

$dbInput=[];

$lines = explode("\n", $input);
//or for a file, $lines = file('file.path', FILE_IGNORE_NEW_LINES);

foreach($lines as $line){
    if(substr($line, 0, 1) == '#') continue;

    list($id, $crumb) = explode('-', $line);
    $id = trim($id);
    $crumb_parts = array_map('trim',explode('>', $crumb));
    $title = array_pop($crumb_parts);
    $parent = array_pop($crumb_parts);
    $parent_id = isset($dbInput[$parent])? $dbInput[$parent][':id'] : null;

    $dbInput[$title] = [
        ':id'       =>  $id,
        ':parent'   =>  $parent_id,
        ':title'    =>  $title,
    ];
}
$pdo = new PDO('mysql:host=localhost;dbname=dbname','usr','pass');

$sth = $pdo->prepare("INSERT INTO tree (id, parent, title) VALUES (:id, :parent, :title)");
foreach($dbInput as &$input){
    $sth->execute($input);
}
echo 'done';