Hooks and filters – E-Dynamics wordpress

EME provides a number of hooks and filters so you can customize a number of things to your liking. For a howto in general about hooks and filters, see here for actions and here for filters.
Below is a list of all possible hooks and filters (with a number of examples) that you can use to change how EME behaves. To avoid having to redefine your hooks and filters when you update WP, EME or your theme, you have some options:

Preferred option: add the code snippets to a folder called wp-content/uploads/events-made-easy/includes. Any file in there that starts with “eme_” and ends on “.php” will get included by EME.
Add them to your theme’s functions.php file (use a child theme, so your changes won’t get lost when the theme gets updated)
Use a plugin like Code Snippets

Hooks

As an example, if you would want to hook into eme_insert_rsvp_action, you would add something like this to your theme’s functions.php:


add_action('eme_insert_rsvp_action','do_my_stuff');
function do_my_stuff($booking) {
 ....
}

If the action hook or filter needs more (or less) than 1 variable (1 is the default), you need to specify the number of arguments (it is in the explanation) and the priority. Example (10 is the default priority, and the hook eme_insert_recurrence_action needs 2 arguments):


add_action('eme_insert_recurrence_action','do_my_stuff',10,2);
function do_my_stuff($event,$recurrence) {
 ....
}

The following hooks are available:

eme_insert_event_action (1 parameter: $event)
An example for how to use this to send mail to all users for new events (change “html” to “text” in the eme_replace_event_placeholders call for $body, if you don’t have EME configured to end out html mails):


add_action('eme_insert_event_action','eme_mail_event');
function eme_mail_event ($event) {
   $contact = eme_get_event_contact ($event);
   $contact_email = $contact->user_email;
   $contact_name = $contact->display_name;
   $subject_format="This is the new event called ' #_EVENTNAME '";
   $body_format="This is the new event called ' #_EVENTNAME '";

   $subject=eme_replace_event_placeholders($subject_format, $event, "text");
   $body=eme_replace_event_placeholders($body_format, $event, "html");
   $blogusers = get_users();
   foreach ( $blogusers as $user ) {
      eme_queue_mail($subject,$body, $contact_email, $contact_name, $user->user_email, $user->display_name);
   }
}

Or to send it to the EME group with ID 5 (change “html” to “text” in the eme_replace_event_placeholders call for $body, if you don’t have EME configured to end out html mails):


add_action('eme_insert_event_action','eme_mail_event');
function eme_mail_event ($event) {
   $contact = eme_get_event_contact ($event);
   $contact_email = $contact->user_email;
   $contact_name = $contact->display_name;
   $subject_format="This is the new event called ' #_EVENTNAME '";
   $body_format="This is the new event called ' #_EVENTNAME '";

   $subject=eme_replace_event_placeholders($subject_format, $event, "text");
   $body=eme_replace_event_placeholders($body_format, $event, "html");
   $person_ids=eme_get_groups_person_ids(5);
   foreach ( $person_ids as $person_id ) {
      $person=eme_get_person($person_id);
      $person_name=eme_format_full_name($person['firstname'],$person['lastname']);
      eme_queue_mail($subject,$body, $contact_email, $contact_name, $person['email'], $person_name);
   }
}

eme_update_event_action (1 parameter: $event)
eme_delete_event_action (1 parameter: $event)
eme_fs_submit_event_action (1 parameter: $event), executed when an event is entered via the frontend submit form
eme_insert_recurrence_action (2 parameters: $event,$recurrence)
eme_update_recurrence_action (2 parameters: $event,$recurrence)
eme_delete_recurrence_action (2 parameters: $event,$recurrence)

eme_insert_rsvp_action (1 parameter: $booking), executed after inserting rsvp info into the db.
An example for how to use this to implement discounts (but please do use eme_discount_* filters to better implement discounts):


add_action('eme_insert_rsvp_action', 'my_eme_discount_function');
function my_eme_discount_function($booking) {
   global $wpdb;
   $bookings_table = $wpdb->prefix.BOOKINGS_TBNAME;
   $where = array();
   $fields = array();

   $booking_id = $booking['booking_id'];
   $event_id = $booking['event_id'];

   if ($event_id == 5) {        /* put in the event_id that needs processing, or leave out this line to process all events */
      //echo 'EVENT ID='.$event_id .' Booking_id = '.$booking['booking_id'];

      $seats=$booking['booking_seats'];

      // more than 2 seats, then the discount is 5 per seat
      if ($seats> 1)
          $discount = 5*$seats;

        // below a small example to check own input
	//$coupon = "";
        //$answers = eme_get_booking_post_answers($booking);
        //foreach ($answers as $answer) {
        //    if ($answer['field_id'] == 49) {
        //       $coupon = $answer['answer'];
        //    }
        //}
        // now check $coupon for your wanted value

      $fields['discount'] = $discount;
      $where['booking_id'] = $booking['booking_id'];
      $wpdb->update($bookings_table, $fields, $where);
   }
   return;
}

For multiseat events (and possibly multiprice), the discount code is similar:


add_action('eme_insert_rsvp_action', 'my_eme_discount_function');
function my_eme_discount_function($booking) {
   global $wpdb;
   $bookings_table = $wpdb->prefix.BOOKINGS_TBNAME;
   $where = array();
   $fields = array();

   $booking_id = $booking['booking_id'];
   $event_id = $booking['event_id'];

   if ($event_id == 5 && eme_is_event_multiseats($event_id)) {
      /* put in the event_id that needs processing, or leave out this line to process all events */
      $seats=eme_convert_multi2array($booking['booking_seats']); // $seats is now an array for the different seat categories defined

      // example: more than 2 seats in the first category and 3 seats in the second, then the discount is 2 per seat in the first
      // and 3 in the second, or in the case all prices are the same for the different seat categories, set the discount to 5 per seat
      if ($seats[0]> 2 && $seats[1]> 3) {
          if (eme_is_multi($booking['booking_price'])) {
             $discount = 2*$seats[0];
             $discount += 3*$seats[1];
          } else {
             $discount = 5*eme_get_total($seats);
          }
      }

      $fields['discount'] = $discount;
      $where['booking_id'] = $booking['booking_id'];
      $wpdb->update($bookings_table, $fields, $where);
   }
   return;
}

eme_update_rsvp_action (1 parameter: $booking), executed after updating booking info
eme_trash_rsvp_action (1 parameter: $booking), executed just before moving a booking to trash
eme_delete_rsvp_action (1 parameter: $booking), executed after purging a booking from trash
eme_trash_person_action (1 parameter: $person), executed just before moving a person to trash
eme_ipn_action (1 parameter: $booking), executed after a successfull IPN arrived from one of the payment gateways
eme_ipn_fs_event_action (1 parameter: $event), executed when an frontend submitted event is successfully paid for via an online payment gateway (only those that send out payment notifications of course)
eme_insert_member_action (1 parameter: $member), executed after a member signed up. In the defined function, you can also call eme_get_member_answers($member[‘memberid’])
eme_delete_member_action (1 parameter: $member), executed just before a member is removed. In the defined function, you can also call eme_get_member_answers($member[‘memberid’])

eme_rsvp_email_action (4 parameters: the booking, the action, the calculated person email subject and body), you can hook into the mail action and based on the action itself, execute custom code (like sending a text). An example:


  add_action('eme_rsvp_email_action','do_my_stuff', 10, 4);
  function do_my_stuff($booking,$action,$subject,$body) {
        $person = eme_get_person ($booking['person_id']);
        $event = eme_get_event($booking['event_id']);
        // let's send texts to the person in case it is a reminder email
        if ($action == 'reminderBooking') {
            // send_text_to_number is a function you need to write
            send_text_to_number($person['phone'],"this is text");
        }
         ....
  }

eme_member_email_action (4 parameters: the member, the action, the calculated person email subject and body), you can hook into the mail action and based on the action itself, execute custom code (like sending a text). An example:


  add_action('eme_member_email_action','do_my_stuff', 10, 4);
  function do_my_stuff($member,$action,$subject,$body) {
        $person = eme_get_person ($member['person_id']);
        $membership = eme_get_membership($member['membership_id']);
        // let's send texts to the person in case it is a reminder email
        if ($action == 'expiration_reminder') {
            // send_text_to_number is a function you need to write
            send_text_to_number($person['phone'],"this is text");
        }
         ....
  }

The action strings are (currently): expiration_reminder, markPaid, resendPaidMember, extendMember, updateMember, stopMember, ipnReceived, newMember, resendPendingMember.

eme_frontend_cancel_booking_action (1 parameter: the booking being canceled), this allows to execute an action before the booking gets cancelled in the fromtend by the user (for example, force a refund). An example where the booker is refunded:
```
  add_action('eme_frontend_cancel_booking_action','do_my_stuff');
  function do_my_stuff($booking) {
        eme_refund_booking( $booking );
  }
```
If the action hook “eme_trash_rsvp_action” is also defined, that one gets executed too (since the booking gets in fact moved to trash).

eme_events_daily_action, eme_members_daily_action and eme_daily_action: actions that run on a daily basis. Neither takes any arguments, so all 3 result in the same thing: something being run once a day (but might be easier to “split” code logically if needed). An example that gets the list of rsvp-events and does something then:


add_action('eme_events_daily_action','my_custom_eme_events_daily_action_function', 10, 0);
function my_custom_eme_events_daily_action_function() {
        $events = eme_get_events( extra_conditions: 'event_rsvp=1');
        foreach ($events as $event) {
            // do something here, send mails, check attendees, ...
            $bookings = eme_get_bookings_for($event['event_id']);
        }
}

eme_ical_header_action: allows to add custom headers to the ical output by just echo-ing them. An example to add a custom calendar name:


add_action('eme_ical_header_action','my_custom_eme_ical_header_action_function', 10, 0);
function my_custom_eme_ical_header_action_function() {
        $cal_name = "my custom ical name";
        echo eme_esc_ical('NAME:', $cal_name");
        echo eme_esc_ical('X-WR-CALNAME:', $cal_name");
}

Hints:
– get the event from the booking id by using this: $event = eme_get_event_by_booking_id($booking['booking_id']);
– get the answer for a member by calling: $answers = eme_get_member_answers($member_id);
– get the answer for a person by calling: $answers = eme_get_person_answers($person_id);
– get the answer for a booking by calling: $answers = eme_get_booking_answers($booking_id);
– get the answer for a event by calling: $answers = eme_get_event_answers($event_id);
– get the answer for a location by calling: $answers = eme_get_location_answers($location_id);
– get the answer for a membership by calling: $answers = eme_get_membership_answers($membership_id);
– get the active member matching the current logged in user and membership id by calling: $member = eme_get_member_by_wpid_membershipid($wp_id, $membership_id);. The third argument to eme_get_member_by_wpid_membershipid is a comma-separated list of status you want (combo if: EME_MEMBER_STATUS_ACTIVE , EME_MEMBER_STATUS_GRACE, EME_MEMBER_STATUS_PENDING, EME_MEMBER_STATUS_EXPIRED) and if not specified will be “EME_MEMBER_STATUS_ACTIVE , EME_MEMBER_STATUS_GRACE”.

Filters

Example usage


add_filter('eme_event_filter','do_my_stuff');
function do_my_stuff($event) {
 ....
}

If the filter needs more than 1 variable, you need to specify the number of arguments (it is in the explanation) and the priority. Example (10 is the default priority, and the filter needs 2 arguments):


add_filter('eme_a_filter_example_filter','do_my_stuff',10,2);
function do_my_stuff($event,$booker) {
 ....
}

The following filters are available:

eme_insert_discount_filter, eme_insert_event_filter, eme_insert_location_filter, eme_insert_person_filter, eme_insert_group_filter, eme_insert_member_filter. Takes 1 parameter: the event/locationi/discount/person/group/member as an array. The return value should be the modified array. These filers are executed just before the event/locationi/discount/person/group/member is entered into the database, allowing you to change certain values on the fly (e.g. setting a default value).
eme_event_filter (1 parameter: $event (array), return value should be modified array). This filter is executed just before showing the info for an event.
eme_event_list_filter (1 parameter: $events (array of events), return value should be modified array)
eme_location_filter (1 parameter: $location (array), return value should be modified array)
eme_location_list_filter (1 parameter: $locations (array of locations), return value should be modified array)
eme_directions_form_filter (1 parameter: generated html for the directions form, return value should be modified html)
eme_add_booking_form_filter and eme_cancel_booking_form_filter (1 parameter: generated html for the add or delete booking form, return value should be modified html)
eme_email_obfuscate_filter (1 parameter: email address or phone). If defined, the standard ascii obfuscating won’t take place and you can use your own filters, eg. from an obfuscating plugin, if you define it in functions.php:
add_filter( ’eme_email_obfuscate_filter’, ‘c2c_obfuscate_email’ );
This filter is used to alter the obfuscation for email address and phone in mails sent.

eme_eval_booking_form_post_filter and eme_eval_multibooking_form_post_filter, which happen just after the POST of the booking form (1 arg: $event for eme_eval_booking_form_post_filter, or $events for eme_eval_multibooking_form_post_filter; containing the event(s) details that are being booked for).
The return should be an array, with the first element of that array indicating that your evaluation is successful or not (1 or 0) and the second parameter a string indicating the reason if not successfull. Returning the array happens like this for success:
array(0=>1,1=>'');
or for failure:
array(0=>0,1=>'The eval failed because of ....');
To simplify some more, a simple “return” or end-of-function is also considered as “success”
For example, put the following in your theme functions.php to prevent double name/email combo’s to register twice (EME can check for this, but only if you require WP membership, otherwise it’s just too easy to change a letter in the name):


add_filter('eme_eval_booking_form_post_filter','do_my_stuff');
function do_my_stuff($event) {
    $event_id=$event['event_id'];
    $already_registered=0;

    // only do a specific event
    if ($event_id != 5) return;

    // get all attendees
    $attendees = eme_get_attendees_for($event_id);
    $booker = eme_get_person_by_post();
    if (!empty($booker)) {
       foreach ($attendees as $attendee) {
          if ($attendee['person_id']==$booker['person_id'])
             $already_registered=1;
       }
    }

    if (!$already_registered) {
       // eval is success
       return array(0=>1,1=>'');
       // or just use return, is ok too
       // return;
    } else {
       // bad form entry
       return array(0=>0,1=>'Already registered');
    }
}

An example for multibooking, to check that at least 1 seat is booked in total:


add_filter('eme_eval_multibooking_form_post_filter','do_my_stuff');
function do_my_stuff($events) {
    // it is recommended to add a hidden field in your form, and we check on that
    if (!isset($_POST['my_hidden_field'])) return;

    // as an example, let's just count the number of seats booked in total, to be sure
    $total_booked=0;
    foreach ($_POST['bookings'] as $key=>$val) {
        // format posted: $_POST['bookings'][$event_id]['bookedSeats']
        $total_booked+=$_POST['bookings'][$key]['bookedSeats'];
    }

    // do something for all events being registered for
    // foreach ($events as $event) {
    // .... (see the example for eme_eval_booking_post_filter)
    // }
    if ($total_booked>0) {
       // eval is success
       return array(0=>1,1=>'');
    } else {
       // bad form entry
       return array(0=>0,1=>'Not enough seats registered');
    }
}

eme_event_preinsert_filter (1 parameter: $event), taking place just before the event is inserted in the DB. The return should be the modified $event array.
eme_event_preupdate_filter (1 parameter: $event), taking place just before the event is updated in the DB. The return should be the modified $event array.
eme_add_currencies (1 parameter: array of currencies), so you can add extra currencies to the list. Be aware that not all payment portals support all currencies.
Example: to add Ghanaian Cedi (GHS) to the list of currencies, add the following to your theme’s functions.php:
```
  function my_eme_add_currencies($currencies){
      $currencies['GHS'] = 'Ghanaian Cedi';
      return $currencies;
  }
  add_filter('eme_add_currencies','my_eme_add_currencies');
```
eme_add_zero_decimal_currencies (1 parameter: array of currencies), to add your own definition of a currency to the list of currencies that don’t allow decimals.
Example: to add the code for Ghanaian Cedi (GHS) to the list of currencies, add the following to your theme’s functions.php:
```
  function my_eme_add_zero_decimal_currencies($currencies){
      $currencies[] = 'GHS';
      return $currencies;
  }
  add_filter('eme_add_zero_decimal_currencies','my_eme_add_zero_decimal_currencies');
```
eme_add_currency_codes (1 parameter: array of currencies), so you can add extra currency codes to the list according to the ISO 417 standard (see https://en.wikipedia.org/wiki/ISO_4217 ). If you add currencies using the filter eme_add_currencies, you should also add the new currency code using this filter. Currently these codes are only used for FirstData payments.
Example: to add the code for Ghanaian Cedi (GHS) to the list of currencies, add the following to your theme’s functions.php:
```
  function my_eme_add_currency_codes($currencies){
      $currencies['GHS'] = '936';
      return $currencies;
  }
  add_filter('eme_add_currency_codes','my_eme_add_currency_codes');
```
eme_offline_payment_gateways (1 parameter: array with offline payment gateways): should return a modified array containing the list of offline payment gateways. This might prove usefull when custom payment gateways are added.
eme_configured_payment_gateways (1 parameter: array with currently configured payment gateways): should return a modified array containing the list of configured payment gateways. This helps in preselecting a payment gateway for new events/memberships. This might prove usefull when custom payment gateways are added. The list also influences the order in which the payment buttons are rendered in the frontend payment forms.
eme_categories_filter (1 parameter: array of categories) executed when searching for the categories (e.g. when creating an event). With this, you can e.g. limit the categories shown when creating an event or location or … .
eme_rsvp_email_body_text_filter and eme_rsvp_email_body_html_filter (1 parameter: mail body being sent), taking place just before a mail is being sent (all mails: pending, success, cancelled, to contact person or booker, …). The return should be the modified mail body. If the returned body is empty, no mail will be sent.
email filters eme_rsvp_email_text_xxx_filter and eme_rsvp_email_html_xxx_filter with “xxx” being one of:
confirmed_body,updated_body,pending_body,denied_body,cancelled_body
confirmed_subject,updated_subject,pending_subject,denied_subject,cancelled_subject
contact_body,contact_cancelled_body,contact_pending_body
contact_subject,contact_cancelled_subject,contact_pending_subject, userconfirmation_pending_subject, userconfirmation_pending_body, pendingbutpaid_subject, pendingbutpaid_body, contact_pendingbutpaid_subject, contact_pendingbutpaid_body, eme_rsvp_email_from_pending_to_waitinglist_subject, eme_rsvp_email_from_pending_to_waitinglist_body, eme_rsvp_email_from_waitinglist_to_pending_subject, eme_rsvp_email_from_waitinglist_to_pending_body
These filters also take 1 parameter (the mail body being sent), but allow finer control than eme_rsvp_email_body_text_filter and eme_rsvp_email_body_html_filter, since you can choose which type of mail to filter. Also: if the returned body is empty, no mail will be sent.
The “pendingbutpaid” filters are for the edge case when a payment arrives for a pending booking for an event with auto-approve active but the event is fully booked so the booking can’t get approved automatically. By default this mail will only be sent to the contact person (and is empty for the booker) and can only be changed via this filter.
eme_events_format_prefilter (2 parameters: $format,$event): an initial filter for the events format, in case people want to change anything before the placeholders get replaced by EME.
eme_cal_format_prefilter (3 parameters: $format,$event,$calday): an initial filter for the calendar format, in case people want to change anything before the placeholders get replaced by EME.
eme_extra_event_headers_filter (2 parameters: $current_headers, $event): allows to change the headers of an event via extra code if needed ($current_headers and $event are both arrays). Return should be the modified array of headers. Example to just add a simple fixed header:
```
function my_eme_extra_event_headers_filter($headers,$event) {
    $headers['my_custom_header']="my_value";
    return $headers;
}
add_filter('eme_extra_event_headers_filter','my_eme_extra_event_headers_filter',10,2);
```
eme_extra_event_headers_json_filter (2 parameters: $current_headers, $event): allows to change the google-related json+ld headers of an event via extra code if needed ($current_headers and $event are both arrays). The difference with eme_extra_event_headers_filter is that this filter results in headers for the google-related json+ld output, but the usage is identical (so the example of eme_extra_event_headers_filter applies here too). An extra example adding the json-ld attributes person and eventstatus, based on your own custom event fields (in this case called ‘performer’ and ‘eventstate’, for all values for those fields I refer to https://developers.google.com/search/docs/data-types/event ):
```
function eme_3cs_google_headers($current_headers, $event) {
        $performer=array();
        $performer["@type"]="Person";
        $performer["name"]="#_FIELD{performer}";
        $current_headers["performer"]=$performer;
	$current_headers['eventStatus']="#_FIELD{eventstate}";
	return $current_headers;
}
add_filter('eme_extra_event_headers_json_filter','eme_3cs_google_headers', 10, 2);
```

eme_csv_header_filter and me_csv_footer_filter (1 parameter: $event): used to add a first or last line to the CSV output, in case you want to add event info to the csv output

function my_eme_csv_header($event) {
    $my_line=array();
    $my_line[]=$event['event_id'];
    $my_line[]=$event['event_name'];
    return $my_line;
}
add_filter('eme_csv_header_filter','my_eme_csv_header');

eme_csv_column_filter: takes 3 arguments: one line of the csv output of the bookings, the event, and the line number in the csv output (the filter is applied for each line of the csv output). This allows you to play with the rendered CSV output. Example:

function my_eme_csv_column_filter($line,$event,$line_nbr) {
   // you can use $event to change the filtering based on the event id or category or whatever
   // you can use $line_nbr to change something on a specific line
   // example where we just switch columns 1 and 2 (index starts at 0)
   $out_line=$line;
   $out_line[1]=$line[2];
   $out_line[2]=$line[1];
   // we don't want column 5
   unset($out_line[5]);
   return $out_line;
}
add_filter('eme_csv_column_filter','my_eme_csv_column_filter',10,3);

discount filters: for discounts of type ‘code’ you can create a filter like ’eme_discount_xxx’ with ‘xxx’ being the name of the discount, see the chapter on discounts for this
eme_cal_full_yearmonth and eme_cal_small_yearmonth: used to change the header shown in the full/small calendar. Has 3 parameters: current string shown, selected month, selected year
eme_calday_url_class_filter: can be used to class for calendar day-urls (e.g. for setting “noindex” or so, searchbots don’t execute js so the class needs to be added via code). Has 1 parameter: the current class
eme_event_categories_sep_filter, eme_event_categorydescriptions_sep_filter, eme_linked_event_categories_sep_filter (1 parameter: the current separator): these control the separator for #_EVENTCATEGORIES (default: “, “), #_EVENTCATEGORYDESCRIPTIONS (default: “, “) and #_LINKEDEVENTCATEGORIES (default: “, “)

Payment description filters for RSVP and member signup: eme_rsvp_paymentform_description_filter and eme_member_paymentform_description_filter. These filters take 3 arguments: the current payment description, the payment and the gateway name. Example to modify:

function my_eme_member_payment_descr($description,$payment,$gateway_name) {
    // $gateway_name is e.g. 'mollie', so you can change the description based on the gateway used if desired
    $member = eme_get_member_by_paymentid($payment['id']);
    $membership = eme_get_membership($member['membership_id']);
    $person = eme_get_person($member['person_id']);
    $description = .... // change this
    return $description;
}
add_filter('eme_member_paymentform_description_filter','my_eme_member_payment_descr',10,3);
function my_eme_rsvp_payment_descr($description,$payment,$gateway_name) {
    // $gateway_name is e.g. 'mollie', so you can change the description based on the gateway used if desired
    $booking_ids = eme_get_payment_booking_ids($payment['id']);
    $booking = eme_get_booking($booking_ids[0]);
    $event = eme_get_event($booking['event_id']);
    $person = eme_get_person($booking['person_id']);
    $description = .... // change this
    return $description;
}
add_filter('eme_rsvp_paymentform_description_filter','my_eme_rsvp_payment_descr',10,3);

Based on the example above, you now have $person (which is an array containing the personal info), $event, etc … so if you want to change anything to the description: you can use anything to your liking now.

eme_field_value_filter and eme_admin_field_value_filter. These take 3 arguments: the formfield ($formfield, array), the form POST fieldname (a string) and the current value (a string). Using these filters (eme_admin_field_value_filter is applied only in the admin backend, eme_field_value_filter only in the frontend), you can change the value of certain form fields by looking up other info from other tables/posts and based on the formfield, the userid, …
Example:

function my_formfield_filter($formfield,$postfield_name,$value) {
    // do a print_r of $formfield, etc ... to see the content. Check the wordpress userid with wp_get_current_user() and do all magic you want :-)
    // as an example, let's change the value of a field if it is called 'testfield')
    if ($formfield['field_name']=='testfield') {
       return "EEE";
    } else {
       return $value;
    }
}
add_filter('eme_field_value_filter','my_formfield_filter',10,3);

eme_ical_filter. Takes one argument: the current ical-representation of a single event in a list of ical entries generated by the eme ical feed (generated with ICAL). This lets you influence each line of an ical entry in the ical feed of events, so you can add/remove/change lines per entry.
Example where we add and remove a specific line (read the comments in the example):

function my_ical_filter($ical_entry) {
    // do a print_r of $ical_entry to see the content
    // as an example, let's add a line "CLASS:PUBLIC"
    $ical_entry .= eme_esc_ical("CLASS:PUBLIC");
    // other example: remove lines that contains "ORGANIZER"
    $ical_entry = preg_replace('/ORGANIZER.*\r\n/','',$ical_entry);
    return $ical_entry; 
}
add_filter('eme_ical_filter','my_ical_filter');

eme_excerpt_length. Takes one argument: the excerpt length. Default length is 55 characters
eme_week_scope_filter, eme_month_scope_filter, eme_year_scope_filter. Takes one argument: the current scope array used to create the relevant dropdown in the form generated by the eme_filter shortcode. This allows you to add/remove weeks/months/years to the scope being used.
The elements in the returned array must have the format “YYYY-MM-DD–YYYY-MM-DD” and a label value. Example:
```
array( "2020-01-01--2020-12-31"=>"2020" , "2021-01-01--2021-12-31"=>"2021");
```
eme_payment_gateways. Takes one argument: the current payment gateways as an associative array. It can be used to remove payment gateways from the options, or change their order. The list also influences the order in which the payment options are presented in the backend.
eme_event_formfields, eme_location_formfields and eme_membership_formfields filters. Each takes 1 argument: the current list of formfields of type events, locations or memberships in the form of an array. The return should be a modified array of formfields (so you can change e.g. the sequence).

eme_filter_mail_options. Takes one argument: the current mail configured options as an associative array. It can for example be used to change mail settings per domain. An example of changing the settings for e.g. microsoft domains:

add_filter ('eme_filter_mail_options','eme_my_filter_mail_options');
function eme_my_filter_mail_options($mail_options) {
        $fqdn = strtolower(substr(strrchr($mail_options['toMail'], "@"), 1));
        $ms_array=["hotmail.com","live.be","outlook.com","hotmail.be","live.nl","msn.com","outlook.be"];
        if (in_array($fqdn,$ms_array)) {
                   $mail_options['smtp_host'] = "my.other.mail.server";
                   $mail_options['smtp_encryption']  = "tls";
                   $mail_options['smtp_verify_cert'] = false;
                   $mail_options['smtp_port']        = 587;
                   $mail_options['smtp_auth']        = true;
                   $mail_options['smtp_username'] = "my username";
                   $mail_options['smtp_password'] = 'my password';
        }
        return $mail_options;
}

The complete list of options:

     $mail_options=array(
           'fromMail',
           'fromName',
           'toMail',
           'toName',
           'replytoMail',
           'replytoName',
           'bcc_addresses',
           'mail_send_method', // smtp, mail, sendmail, qmail, wp_mail
           'send_html',        // true or false
           'smtp_host',
           'smtp_encryption',  // none, tls or ssl
           'smtp_verify_cert', // true or false
           'smtp_port',
           'smtp_auth',        // 0 or 1, false or true
           'smtp_username',
           'smtp_password',
           'smtp_debug',      // true or false
   );

eme_wp_userdata_filter: allows you to set extra info for the WP user being created after a booking (if that option is set). The current EME person is given as argument (array), the result should be an array that is accepted by wp_update_user
```
add_filter('eme_wp_userdata_filter','eme_my_wp_userdata_function');
function eme_my_wp_userdata_function($person){
   $userdata=array();
   $userdata['display_name']=$person['firstname'].' '.substr($person['lastname'],0,1);
   return $userdata;
}
```
Remark: last name and first name userdata properties are set after the filter (those need to be the same as the person in EME).
eme_fs_categories_filter: to filter the categories, see also eme_categories_filter
eme_fs_event_insert_filter: executed just before insert of the new event in the database (so you can change certain properties by default). See also eme_insert_event_filter