Using get_option() for check box field

Question

This may not exactly answer the question, but let’s see the issues with your code:

If you want to save the data in the same format as the default value ($fields_default), then:

Start your foreach like so: foreach ( $orderdescider as $i => $item ).

Then inside that foreach, $id and $checkbox should always be set and defined like so:

$id = isset( $item['id'] ) ? $item['id'] : '';
$checkbox_check = isset( $item['checkbox_check'] ) ? $item['checkbox_check'] : '';

And use the appropriate value in the field’s name:

<input type="hidden" name="orderdescider[<?php echo $i; ?>][id]"
  value="<?php echo $id; ?>">

<input type="checkbox" name="orderdescider[<?php echo $i; ?>][checkbox_check]"
  value="1" ...>

For the checkbox fields, you can use this format when writing the markup:

<input type="checkbox" value="{value}"<?php // wrapped for clarity
  checked( '{value}', '{current/saved value}' ) ?> ...>

so in your case, it would look like this:

<input type="checkbox" name="orderdescider[<?php echo $i; ?>][checkbox_check]"
  value="1"<?php checked( '1', $checkbox_check ) ?> ...>

where 1 is the {value}, and $checkbox_check is the {current/saved value}.

(See the reference for more details about using the checked() function.)

Hope that helps, and here’s the full foreach code I used for testing: (I omitted the field’s id, but make sure to use unique values)

foreach ($orderdescider as $i => $item) {
    $id = isset( $item['id'] ) ? $item['id'] : '';
    $checkbox_check = isset( $item['checkbox_check'] ) ? $item['checkbox_check'] : '';
    ?>
    <li class="sortable-item flexit">
        <div class="form-check">
            <input type="hidden" name="orderdescider[<?php echo $i; ?>][id]"
              value="<?php echo $id; ?>">
            <input type="checkbox" name="orderdescider[<?php echo $i; ?>][checkbox_check]"
              value="1"<?php checked( '1', $checkbox_check ) ?> class="form-check-input">
        </div>
    </li>
    <?php
}