javascript - Use SetInterval when the If condition is True -

is possible if value of $new changed var updatechart function reload again , again goes var check function , again have same condition on it.

var updateinterval = 3000;   var updatechart = function() {       var check = function() {         if(<?php echo $new; ?>).change(function(){           setinterval(function(){updatechart()}, 1000);         });       }     dps.push(<?php echo $str; ?>);     chart.render();    }; 

will appreciated thanks.

so want update chart value has been written on server-side, right? mentioned in comment, using php statements in js block not work php code run on page load , won't change afterwards. instead, should use two-step approach:

• use recurring ajax call poll changes
• create php page reports changes

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js code (using jquery):

window.setinterval(function() {   $.ajax('change-listener.php', {     success: function(data) {       if (data.changed) {         for(var in data.newvalue) {           dps.push(data.newvalue[i]);         }         chart.render();       }     }   }); }, 3000);  

check rows have been written in given time span (assuming table right records has timestamp) , return corresponding values via json js script:

php code:

$query= 'select strvalue [yourtable] created > date_sub(now(),interval 3 second)';  $data= array(); if ($result = $mysqli->query($query)) {      if (mysqli_num_rows($result)) {         $data['changed']= true;         while($obj = $result->fetch_object()){              $data['newvalues'][]= $obj->strvalue;         }      } else {         $data['changed']= false;     } }  $result->close();  header('content-type: application/json'); print json_encode($data); 

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an alternate way store newly created values inside user's session:

php code, part 1 (inside script handles storing of new values):

session_start();     $_session['newvalues'][]= $str; 

php code, part 2 (instead of polling database, poll session):

session_start();   if (isset($_session['newvalues'])) {   $data['changed']= true;   $data['newvalues']) $_session['newvalues'];   unset($_session['newvalues']; } else {   $data['changed']= false; } 

the second approach pure single-user scenario: php script polls changes, changes returned once , list of changes reset never return same values twice.