virtuemart register form if country is china will show another input text

[florihana]

Using joomla: 3.6
VirtueMart 3.0.18

Hi experts,

Sorry I had to ask but look for the solutions couple hours, 
I would like to if user go to virtuemart registration form, choose country part, like choice China for example
then will show another input: please enter your Chinese address

see the picture

[Jumbo!]

You need to use some custom Javascript for this. The script will depend on your template's layout and chinese address field id. Post the page link.

[florihana]

Thank you Jombo,

the problem is I could not find which file in Joomla could add this event,
so far there is vmsite.js file: /components/com_virtuemart/assets/js/vmsite.js

but how to find the country_id data?
In database virtuemart_country_id, china id is 44

so I was thinking doing:
if ( country_id == 44) {
    jQuery('form#adminForm input#address_chinoise_field').show;
} 

but finding country id data seems obstacle

thank you