Require captions for a photo field

ON('validate-record', function (event) {
  // if there are any photos, loop through the $photos objects and test the caption property for null
  if ($photos) {
    for (var i = 0; i < $photos.length; i++) {
      // if caption is missing, alert the user and prevent the record from saving
      if ($photos[i].caption === null) {
        INVALID('All photos must have captions!');
      }
    }
  }
});

ON('validate-record', function (event) {
  // loop through the photo fields
  DATANAMES('PhotoField').forEach(function(dataName) {
    // get the photo field value
    var photos = VALUE(dataName);
    // if there are any photos, loop through the photo objects and test the caption property for null
    if (photos) {
      for (var i = 0; i < photos.length; i++) {
        // if caption is missing, alert the user and prevent the record from saving
        if (photos[i].caption === null) {
          INVALID('All photos must have captions!');
        }
      }
    }
  });
});