Inserting value in a JavaScript variable from php code

Question

I am trying to test the following code for inserting the value from PHP code to my javascript variable x

tested the PHP code, and it's giving the correct output but the alert box in the javascript shows this -

date_sub(curdate(),interval 1 day) and activity=1 group by code having b > 1000"; $query = mysql_query($myquery); if ( ! $myquery ) { echo mysql_error(); die; } $data = array(); for ($x = 0; $x < mysql_num_rows($query); $x++) { $data[] = mysql_fetch_assoc($query); } //echo json_encode($data); echo ''; mysql_close($server); ?>

<html>
  <head>    
    <meta http-equiv="Content-type" content="text/html; charset=utf-8">
    <title>Testing </title>
   
  
    <script type="text/javascript" src="jquery-1.9.1.min.js"></script> 
  </head>
  <body>
  <?php
    $username='user'; 
    $password='pass';   
    $host='xx.xx.xx.xx';
    $database='abc';
    $server = mysql_connect($host, $username, $password);
    $connection = mysql_select_db($database, $server);
    $myquery = 'select code a,sum(fee) b from xyz where date > date_sub(curdate(),interval 1 day) and activity=1 group by code having b > 1000';
    $query = mysql_query($myquery);
    if ( ! $myquery ) {
        echo mysql_error();
        die;
    }
    $data = array();
    for ($x = 0; $x < mysql_num_rows($query); $x++) {
        $data[] = mysql_fetch_assoc($query);    
    }
    //echo json_encode($data);
    echo '<input type="hidden" name="myPhpValue" value="'. json_encode($data) . '">';
    
    mysql_close($server);
    ?>
    
    <script type="text/javascript">
        function test(){
             var x = document.getElementById("myPhpValue").value;
             alert(x);  
        }
        test();

    </script>
  </body>
</html>

you're inserting a value into html, not javascript code. so use `htmlspecialchars` instead of `json_encode` — poncha, Apr 15 '16 at 07:40
i am inserting the value in a javascript variable.. and i tried a ssuggested, it isnt working — cap, Apr 15 '16 at 08:59

score 1 · Accepted Answer · edited Apr 15 '16 at 08:20

1

echo '<input type="hidden" name="myPhpValue" value="'. json_encode($data) . '">';

Then:

var x = document.getElementById("myPhpValue").value;

you need to insert id="myPhpValue", because you used the "getElementById";

edited Apr 15 '16 at 08:20

Ben Rhys-Lewis

3,118
8
34
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answered Apr 15 '16 at 07:46

zzZZ

26
1

score 0 · Answer 2 · answered Apr 15 '16 at 07:54

0

Add ID attribute in the html line

echo '<input type="hidden" name="myPhpValue" value="'. json_encode($data) . '">';

replace the above line by

echo '<input type="hidden" name="myPhpValue" id ="myPhpValue" value="'. json_encode($data) . '">';

answered Apr 15 '16 at 07:54

mad man maddy

13
3

score 0 · Answer 3 · answered Apr 15 '16 at 09:56

0

You are inserting a value into html, not javascript code. Do it like that:

<script type="text/javascript">

function test(){
 var x = <?php echo json_encode($data); ?>;
 alert(x);  
}
test();

</script>

answered Apr 15 '16 at 09:56

Danmoreng

2,367
1
19
32

score 0 · Answer 4 · edited May 23 '17 at 12:24

Server configuration problems

If You are getting php code on client-side (view-source to confirm), then the PHP engine is not working on the server. You should check that php is properly installed on the server and is set as a handler for php files in your web server. This depends on your web server and operating system.

Code problems

Problem #1: your output (echo) is creating an HTML element, not javascript. Hence you should escape the content for HTML - use htmlspecialchars instead of json_encode

Problem #2: you access the element with javascript document.getElementById but your actual element does not have an ID. Hence need to add the id attribute to your html input element.

Solution:

Stage 1: php outputs html - use htmlspecialchars and add id attribute

echo '<input type="hidden" name="myPhpValue" id="myPhpValue" value="'. htmlspecialchars($data) . '">';

Stage 2: javascript accesses html element (this is taken as-is from your code).

var x = document.getElementById("myPhpValue").value;

Side-note

You're using a deprecated mysql extension and should switch to PDO or mysqli instead.

There are numerous discussions both on SO and external resources on the matter.

Just a few:

Inserting value in a JavaScript variable from php code

4 Answers4

Server configuration problems

Code problems

Side-note