html - Input saved to a file and then submitted to the URL on submit -

i have form. right has 1 action , submits inputs url. modified when form completed inputs saved file , submitted url.

<form class="snp-subscribeform snp_subscribeform" action="join.cgi" method="post">     <input name="page" type="hidden" value="1" />     <div>         <input id="snp-firstname" class="snp-field snp-field-firstname " name="firstname" required="" type="text" value="" placeholder="enter first name" />         <input id="snp-lastname" class="snp-field snp-field-lastname " name="lastname" required="" type="text" value="" placeholder="enter last name" />         <input id="snp_email" class="snp-field snp-field-email" name="email" type="text" placeholder="enter email " />         <input id="snp-password" class="snp-field snp-field-password " name="password" required="" type="text" value="" placeholder="select password" />     </div>     <div>         <input class="snp-subscribe-button snp-submit" type="submit" value="continue" data-loading="creating account!" data-success="account created!" />     </div> </form> </div> 

you need use javascript , onclick event submit button retrieve values dom elements interested in , save them file.

here sample of how started:

<input type="submit" name="submit" value="save" onclick="writedata()" />  <script>     function writedata() {     } </script>