How to loop through multiple arrays at the same ti

问题:

Oke so I don't know why this is so hard, all information I find is only for two arrays like array_combine.

I have 3 arrays that I get from dynamically created input fields in a form, so now I want to retrieve the data and print it out like:

Item1 (array1)
Item1 (array2)
Item1 (array3)

Item2 (array1)
Item2 (array2)
Item2 (array3)

But with my code right now it completes one array and than goes to the next.

$article_id = $_REQUEST['article_id'];
$article_descr = $_REQUEST['article_descr'];
$article_ammount = $_REQUEST['article_amount'];

foreach($article_id as $artid) {
    echo = 'Article id: '.$artid.'<br>';
}

foreach($article_descr as $art_descr) {
    echo 'Article description: '.$art_descr.'<br>';
}

foreach($article_ammount as $art_amount) {
    echo 'Article ammount: '.$art_amount.'<br>';
}

回答1:

Since you said that all arrays match by their keys, I will assume you have something like this:

$article_ids = [10, 22, 13];
$article_descriptions = ["this is one", "this is two", "this is three"];
$article_amounts = [20, 10, 40];

Therefore in order to obtain their information in an orderly manner, you would first need to found how many elements there are. We can use the total of the first array, by using count(), then using a for loop to iterate and obtain each array's information.

//get the number of articles
$num = count($article_ids);

//iterate through each article count
for ($i = 0; $i < $num; $i++){
    echo 'Article id: '.$article_ids[$i].'<br>';
    echo 'Article description: '.$article_descriptions[$i].'<br>';
    echo 'Article amount: '.$article_amounts[$i] .'<br>';
}

回答2:

If you are sure that for each item information is under one and the same key in all arrays, you can do following:

$article_id = $_REQUEST['article_id'];
$article_descr = $_REQUEST['article_descr'];
$article_ammount = $_REQUEST['article_amount'];

foreach ($article_id as $id => $value) {
    echo 'Article id: ' . $value . '<br>';
    echo 'Article description: ' . $article_descr[$id] . '<br>';
    echo 'Article ammount: ' . $article_ammount[$id] . '<br>';
}