组织具有类似表格的批量数据的$ _POST输入

Consider a PHP script which generates a form, which looks like a table and has the same recurring rows output many times:

print('<form method="POST" action="index.php">
    <table>
    <tr>
       <th>Row #</th>
       <th><tt>name</tt></th>
       <th><tt>value</tt></th>
    </tr>');

for ( $i = 1; $i <= 4; $i++ )
{
    print('<tr>
        <th>' .$i. '</th>
        <td><input type="text" name="name_' .$i. '" size="20"></td>
        <td><input type="text" name="value_' .$i. '" size="4"></td>
    </tr>');
}

print('</table>
      <input type="submit" name="is_submit" value="Submit">
</form>');

When you submit this form, the $_POST array will look like this:

array (
  'name_1',
  'value_1',
  'name_2',
  'value_2',
  'name_3',
  'value_3',
  'name_4',
  'value_4',
  'is_submit',
);

What I wish to do, it to organize this input so it will look something like this:

array (
  1 => 
  array (
    'name',
    'value',
  ),
  2 => 
  array (
    'name',
    'value',
  ),
  3 => 
  array (
    'name',
    'value',
  ),
  4 => 
  array (
    'name',
    'value',
  ),
);

It means, that every field ending in the same row ID number is grouped together with fellow fields (in the same row) in a two-level deep array.

I have been doodling around with options to solve this and came up with the following "solution" (the organized array (above) is actually a dump of the $output created by this approach):

if ( array_key_exists('is_submit', $_POST) ) // Form is submitted properly
{
    unset($_POST['is_submit']); // Drop the status key

    foreach ( array_keys($_POST) as $key )
    {
        $key_exploded = explode("_", $key); // [0] is key 'basename', [1] is the 'row ID'
        $output[ $key_exploded[1] ][ $key_exploded[0] ] = $_POST[$key];
    }
}

The big problem is that this method looks a bit obfuscated and hard-coded. I think and hope that the more-advanced people around here could guide me for a more dynamical (that unset row is itchy, that I need to call unset() on every non-table row) and better method.

Change these lines:

<td><input type="text" name="name_' .$i. '" size="20"></td>
<td><input type="text" name="value_' .$i. '" size="4"></td>

to

<td><input type="text" name="foobar['.$i.'][name]" size="20"></td>
<td><input type="text" name="foobar['.$i.'][value]" size="4"></td>

$_POST['foobar'] now will have the desired structure.

You could introduce an additional condition in the foreach loop, if you don’t want to change your form:

if ( array_key_exists('is_submit', $_POST) ) // Form is submitted properly
{
    foreach ( array_keys($_POST) as $key )
    {
        $key_exploded = explode("_", $key); // [0] is key 'basename', [1] is the 'row ID'

        // check if keys start with 'name' or 'value'
        if ($key_exploded[0] == 'name' || $key_exploded[0] == 'value')
            $output[ $key_exploded[1] ][ $key_exploded[0] ] = $_POST[$key];
    }
}