php - javascript function inside loop not working -

i displaying online users. when click 1 of user, corresponding user should displayed in text box below. using javascript this, taking first user. when click second user, first user displayed in below text box. why taking first array?

<?php     foreach($query $row)     {     ?>         <input type="text" name="user" id="user" value="<?php echo $row->users;?> onclick="select_online()"> <?php     }     ?>     <script>      function select_online()     {         var user=document.getelementbyid("user").value;         document.getelementbyid("usersonline").value=user;     }     </script>   name:<input type="text" name="usersonline" id="usersonline"> 

first of all, using same id many elements mistake. should make diverse id attribute generated inputs.

second, should use this value of current element:

function select_online() {     var user=this.value;     document.getelementbyid("usersonline").value=user; } 

document.getelementbyid("user") statement select element id attribute equal "user" , same. probably, not want. if understood correctly, want value of clicked element, mentioned before, can achieve using this expression, points clicked element.