Submit Multidimensional Arrays via POST in PHP

When working with PHP forms that have multiple columns and rows of variable lengths, it's necessary to convert the input into a multidimensional array. Here's a solution to this challenge.

First, assign unique names to each column, for example:

This results in HTML similar to:

  
When the form is submitted, you'll obtain arrays like:
$_POST['topdiameter'] = array( 'first value', 'second value' );
$_POST['bottomdiameter'] = array( 'first value', 'second value' );
However, consider using the following format:
name="diameters[0][top]"
name="diameters[0][bottom]"
name="diameters[1][top]"
name="diameters[1][bottom]"
...
With this format, looping through the values becomes more efficient:
if ( isset( $_POST['diameters'] ) )
{
    echo '
';
    foreach ( $_POST['diameters'] as $diam )
    {
        echo '';
        echo '  ';
        echo '  ';
        echo '';
    }
    echo '
', $diam['top'], '
', $diam['bottom'], '
';
}
This solution allows you to easily handle multidimensional arrays submitted via POST forms in PHP.