Looping through multiple POST elements - php

Question

I am trying to figure out how to loop through multiple POST form data that is dynamically pulled from a database and re-submit the modified data to a different table. For some reason (probably old age) I can't seem to come up with a solution that works.
I am already looping out all the records from one table (call it roster) and need to submit it to another table (call it roster2). The form is something similar to this:
<form name="name" action="form.php" method="post">
<input type="text" name="name1" value="15">
<input type="text" name="attended" value="1">
<input type="checkbox" name="nameid_12" value="12">
<input type="text" name="name2" value="8">
<input type="text" name="attended" value="1">
<input type="checkbox" name="nameid_6" value="6">
</form>
The 'name' and 'nameid' fields will always change and the number of records displayed will always be different (one day it could be 5 and the next 100).
What is the best way to loop through the POST data to submit it to the database keeping all the associations intact?
I am relatively new to working with PHP and I can't seem to figure out a good way to do this.

Answer 1

If you're going to generate them dynamically, I would recommend using PHP to place the ID of each form in the inputs on that form. So your original form would end up with these names:
<input type="text" name="name[12]" value="15">
<input type="text" name="attended[12]" value="1">
<input type="checkbox" name="nameid[12]" value="12">
<input type="text" name="name[6]" value="8">
<input type="text" name="attended[6]" value="1">
<input type="checkbox" name="nameid[6]" value="6">
Then your arrays will have keys corresponding to their form's ID. The array structure looks like this.
Array (
[name] => Array ( [12] => 15, [6] => 8 )
[attended] => Array ( [12] => 1, [6] => 1 )
[nameid] => Array ( [12] => 12 [6] => 6 )
)
Now we need to figure out which ids are actually present today. The array_keys() function generates an array of keys from any source array. Keys will be the same for each of the three elements, so I arbitrarily take the keys from [name].
$id_array = array_keys($_POST['name']);
Then, to access each element of the POST array, we'll use a foreach.
foreach ($id_array as $id) {
//assign variables
$name = $_POST['name'][$id];
$attended = $_POST['attended'][$id];
$nameid = $_POST['nameid'][$id];
//store
//Using whichever database style you like. I prefer PDO.
}

Answer 2

You can loop through the fields and retain their keys like so:
foreach ($_POST as $field_name => $field_value) {
// Storage
}