Question

I have a dynamic array $v whose contents change according to a form being submitted. Some forms might have a date field and others may not. For all forms I’m using the same array $v to store values in a key=>value pair and then insert it into the table. So sometimes the array may look like

$v = array('patron_name'=>'some value',
           'place' => 'again some value',
           'pin' => 'blah blah')

and at other times it may look like

$v = array('joomla'=>'some value again',
           'date_applied' => '23/04/2012',
          )

As seen above, the contents vary from form to form. What I’m looking for is to first check if $v contains a value in the form of dd/mm/yyy and if it does, change it to yyyy-mm-dd format to insert into table. I can handle the conversion part, but I’m stuck at determining if $v contains a date or not.

So basically I’m intending to proceed in this way:

if(in_array('date in dd/mm/yyyy format', $v))
{
  // change it to yyyy-mm-dd
}
// and then insert into table
$flag = insert($tablename, $v);

Any help much appreciated. Thanks in advance

Answer 1

Instead of in_array, use preg_replace_callback. Pass the array to it and match for the date format pattern. If the pattern matches, replace it with the callback.

Example (demo):

$v = array(
    'joomla'=>'some value again',
    'date_applied' => '23/04/2012',
);

$result = preg_replace_callback('#^\d{1,2}/\d{1,2}/\d{4}$#', function($match) {
    return DateTime::createFromFormat('d/m/Y', $match[0])->format('Y-m-d');
}, $v);

print_r($result);

On a sidenote, since Y-m-d contains the same values as d/m/Y, you don’t strictly need to use a callback but can just use preg_replace (demo):

$result = preg_replace('#^(\d{1,2})/(\d{1,2})/(\d{4})$#', '$3-$2-$1', $v);

Using a callback would allow you to use an arbitrary date format though.