Combining date and time input data into one field with WPAlchemy metaboxes - meta-boxes

Question

I'm trying to convert a metabox for date and time I'm currently using into a WPAlchemy metabox.
I am currently combining the start date and start time into one field upon save.
This is the old save function:
add_action ('save_post', 'save_event');
function save_event(){
global $post;
// - still require nonce
if ( !wp_verify_nonce( $_POST['event-nonce'], 'event-nonce' )) {
return $post->ID;
}
if ( !current_user_can( 'edit_post', $post->ID ))
return $post->ID;
// - convert back to unix & update post
if(!isset($_POST["startdate"])):
return $post;
endif;
$updatestartd = strtotime ( $_POST["startdate"] . $_POST["starttime"] );
update_post_meta($post->ID, "startdate", $updatestartd );
if(!isset($_POST["enddate"])):
return $post;
endif;
$updateendd = strtotime ( $_POST["enddate"] . $_POST["endtime"]);
update_post_meta($post->ID, "enddate", $updateendd );
Here are the new functions and fields for reference:
$custom_event_metabox = new WPAlchemy_MetaBox(array
(
'id' => '_custom_event_meta',
'title' => 'Event Information',
'template' => /event_meta.php',
'types' => array('event'),
'context' => 'normal',
'priority' => 'high',
'mode' => WPALCHEMY_MODE_EXTRACT,
'save_filter' => 'event_save_filter',
'prefix' => '_my_' // defaults to NULL
));
<li><label>Start Date</label>
<?php $mb->the_field('startdate'); ?>
<input type="text" name="<?php $mb->the_name(); ?>" value="<?php $mb->the_value(); ?>" class="tsadate" />
</li>
<li><label>Start Time</label>
<?php $mb->the_field('starttime'); ?>
<input type="text" name="<?php $mb->the_name(); ?>" value="<?php $mb->the_value(); ?>" class="tsatime" />
<span><em>Use 24h format (7pm = 19:00)</em></span>
</li>
<li><label>End Date</label>
<?php $mb->the_field('enddate'); ?>
<input type="text" name="<?php $mb->the_name(); ?>" value="<?php $mb->the_value(); ?>" class="tsadate" />
</li>
<li><label>End Time</label>
<?php $mb->the_field('endtime'); ?>
<input type="text" name="<?php $mb->the_name(); ?>" value="<?php $mb->the_value(); ?>" class="tsatime" />
<span><em>Use 24h format (7pm = 19:00)</em></span>
The issue I'm facing is I'm not entirely sure if I should be using the save_filter or the save_action, or how I should handle doing this ala WPAlchemy.
This is what I have thus far:
function event_save_filter($meta, $post_id)
{
// the meta array which can be minipulated
var_dump($meta);
// the current post id
var_dump($post_id);
// fix: remove exit, exit here only to show you the output when saving
//exit;
// - convert back to unix & update post
if(!isset($_POST["startdate"])):
return $post;
endif;
$updatestartd = strtotime ( $_POST["startdate"] . $_POST["starttime"] );
update_post_meta($post->ID, "startdate", $updatestartd );
if(!isset($_POST["enddate"])):
return $post;
endif;
$updateendd = strtotime ( $_POST["enddate"] . $_POST["endtime"]);
update_post_meta($post->ID, "enddate", $updateendd );
// filters must always continue the chain and return the data (passing it through the filter)
return $meta;
}
Will this work? And should it be a save_filter or a save_action?
Any insight appreciated ;-)

Answer 1

If you are using WPAlchemy, and all you need is to add new values or update values in your meta data. You can achieve this by adding additional values to the $meta array. When you return it as you should always do when using the save_filter, WPAlchemy will handle the saving of the data.
The main difference between save_filter vs save_action is that with the filter, you must pass back the $meta value, but you can modify the array before doing so, which allows you to save hidden values.
The power in using any of these options is that you can manipulate other aspects of WordPress during a post update and per the values that a user enters in.
Passing back false in the save_filter tells WPAlchemy to stop and not save. An additional difference between the two is also that save_filter happens before the save and save_action happens afterwards.
Here is my attempt at adjusting your code above, obviously you will have to touch it up to make it work for you, please read the comments I've included.
function event_save_filter($meta, $post_id)
{
// the meta array which can be minipulated
var_dump($meta);
// the current post id
var_dump($post_id);
// fix: remove exit, exit here only to show you the output when saving
//exit;
// at this time WPAlchemy does not have any field validation
// it is best to handle validation with JS prior to form submit
// If you are going to handle validation here, then you should
// probably handle it up front before saving anything
if( ! isset($meta['startdate']) OR ! isset($meta['enddate']))
{
// returning false stops WPAlchemy from saving
return false;
}
$updatestartd = strtotime($meta['startdate'] . $meta['starttime']);
// this is an example of setting an additional meta value
$meta['startdate_ts'] = $updatestartd;
// important:
// you may or may not need the following, at this time,
// WPAlchemy saves its data as an array in wp_postmeta,
// this is good or bad depending on the task at hand, if
// you need to use query_post() WP function with the "startdate"
// parameter, your best bet is to set the following meta value
// outside of the WPAlchemy context.
update_post_meta($post_id, "startdate", $updatestartd );
$updateendd = strtotime ($meta['enddate'] . $meta['endtime']);
// similar note applies
update_post_meta($post_id, "enddate", $updateendd );
// filters must always continue the chain and return the data (passing it through the filter)
return $meta;
}