Combining array values? - Part Deux

[duckduckgoose]

I posted an earlier thread on how to combine array values, and marked that thread as resolved. Well, it's not. 🙂 I have a new problem / question...

So, if I print_r($_POST) the values from my form, I'll get something like this:

Array ([example1] => tree [testing1] => green [example2] => flower [testing2] => red [example3] => mountain [testing3] => brown [example4] => ocean [testing4] => blue )

This code:

$key = '';
$i = 0;
$output = array();
foreach($array as $val)
{
if( ($i++ % 2) == 0 ) $key = $val;
else $output[$key] = $val;
} 

Will yield this:

Array ([tree] => green [flower] => red [mountain] => brown [ocean] => blue )

Which is exactly what I wanted.

However, my new question is this:

In the event that the user did not enter a value in one of the fields, how can I set that value to "None". So, if the user never typed "tree" for example, how can I set that to "None"?

I'd like to figure out how to do this after the form has already been submitted, so I don't want to set any default values for the text fields.

[bogu]

foreach($array as $val) 
{ 
    if( ($i++ % 2) == 0 ) $key = $val; 
    else{
        if (empty($key)) $key = 'none';
        if (empty($val)) $val = 'none';
        $output[$key] = $val; 
    }
}