get the value of selected form input then pass it into form input checkbox

[黄祥]

views/form.html

<select id = "table_id" name = "table_id" title = "Table ID" onchange = "ajax('{{=URL(request.controller, target) }}', {{=field_list}}, 'target')" onselect = "jQuery('#month').val()" class = "form-control">

{{for row in rows:}}

<optgroup label = "{{=row.pitch_class}} Tones">

{{

for r in db(table.pitch_class == row.pitch_class).select(cache = cache_db, cacheable = True):

}}

<option value = {{=r.id}} {{='selected' if r.id == 22 else ''}}>

{{=", ".join([row_name for row_name in r.name] ) }}

</option>

{{pass}}

</optgroup>

{{pass}}

</select>

{{selected_table_id = jQuery('#table_id').val() }}

{{for i in range(1, selected_table_id + 1, 1):}}

<input name = "active_string" type = "checkbox" id = {{=i}} value = {{=i}}>

<label for = {{=i}}>{{=i}}</label>

{{pass}}

how to get the value of selected table_id then pass it into selected_table_id variable that can be used for input type checkbox in web2py way ?

thanks and best regards,

stifan