php - how to save data on javascript form -

i have 2 function on js :

<script>     function inc(elem)     {         elem.value++;      }     function dec(elem)     {         if(elem.value>1)         {             elem.value--;         }     } </script> 

and form in html:

<form method="post" action= "tameio.php"  > <input type="hidden" value="0" id="counter" name="counter"> <input type = "submit" value = "nextpage" name = "submit" onclick="inc(document.getelementbyid('counter')); "> <input type = "submit" value = "previouspage" name = "submit" onclick="dec(document.getelementbyid('counter'));"> </form> 

and here php :

<?php if(isset($_post['submit'])) {     echo $_post['counter'];     if($_post['submit'] == 'nextpage'){     ...         } } ?> 

so problem after click nextpage button, 0 goes 1 not stored in form goes 0 again on html . if reclick it going send 1 again. should use ajax instead ?

there no need of that,

<form method="post" action= "tameio.php"  > <input type="hidden" value="<?=$current_page?>" id="counter" name="counter"> <input type = "submit" value = "nextpage" name = "submit" onclick="inc(document.getelementbyid('counter')); "> <input type = "submit" value = "previouspage" name = "submit" onclick="dec(document.getelementbyid('counter'));"> </form> 

and in php:

<?php if(isset($_post['submit'])) {     if($_post['submit'] == 'nextpage')     {         $current_page = $_post['counter'] + 1;     } else {         $current_page = $_post['counter'] - 1;     } } else {     $current_page = 1; } // fetch page data based on current page ...  ?>> 

but recommend instead of post.

<a href="tamieo.php?page=<?=$current_page - 1?>">previous page</a> | <a href="tamieo.php?page=<?=$current_page + 1?>">next page</a> 

and in php:

<?php      if(isset($_get['page']) && $_get['page'] > 0)         $current_page = (int) $_get['page'];     else         $current_page = 1;