php variable display in js

Question

I have been trying to show php variables in javascript like this:

<body>
<?php
$v = "random";
echo "<script language='javascript'> 
document.write('<?php echo($v); ?>');
</script>"
?>
</body>

But this does not show any output in the browser. Why is that?

all the below examples are printing script tag using echo, instead you should use echo only to print the variable value — Mr. Alien, Apr 20 '15 at 03:33

score 5 · Accepted Answer · answered Apr 20 '15 at 03:32

5

Use PHP's string concatenation to do this:

<body>
<?php
$v = "random";
echo "<script language='javascript'> 
document.write('" . $v . "');
</script>"
?>
</body>

answered Apr 20 '15 at 03:32

Sumner Evans

8,951
5
30
47

Adrian Cid Almaguer · Answer 2 · 2015-04-20T03:43:15.533

0

You have some misplaced tags. Try with this code:

<body>
<?php
$v = "random";
echo "<script language='javascript'> 
document.write('$v')";
?>
</script>
</body>

HTML Output:

<body>
<script language='javascript'> 
document.write('random')</script>
</body>

edited Apr 20 '15 at 03:43

answered Apr 20 '15 at 03:31

Adrian Cid Almaguer

7,815
13
41
63

that is wrong as well, stray single quote – Mr. Alien Apr 20 '15 at 03:32
I edit but the code works in my browser – Adrian Cid Almaguer Apr 20 '15 at 03:36
you just copied! also php has nothing to do with browsers – Mr. Alien Apr 20 '15 at 03:37
this code and the previous works and make as output *random* in the browser – Adrian Cid Almaguer Apr 20 '15 at 03:38
nope it won't, if it was working then revert your edit and keep the old code in your answer – Mr. Alien Apr 20 '15 at 03:43
@Mr.Alien I edit again and it works again – Adrian Cid Almaguer Apr 20 '15 at 03:45
that is not the code which you had written when i had commented – Mr. Alien Apr 20 '15 at 03:51

score 0 · Answer 3 · answered Apr 20 '15 at 03:32

0

instead

document.write('<?php echo($v); ?>');

try

document.write('$v');

answered Apr 20 '15 at 03:32

Ayyanar G

1,545
1
11
24

score 0 · Answer 4 · answered Apr 20 '15 at 03:32

You've already opened php with <?php and already invoked the echo call.

It is best to concatenate the variable by closing the quotes and using a period:

echo "<script language='javascript'> 
document.write('". $v ."');
</script>";

Like Mr.Alien said in the comments, it doesn't appear you need to echo the Javascript. You can just invoke PHP where you need to echo the variable. If your install supports short tags, you can do this:

<body>
<script language='javascript'> 
document.write('<?= $v ?>');
</script>
</body>

<?= $v ?> is a short tag for <?php echo $v; ?>

score 0 · Answer 5 · edited May 23 '17 at 11:51

0

for a good practice of programming

and for easy mainting the code between javascript and php

store the php value to a variable and use it in javascript

<?php
    $v = 'random';
?>

<script>
    // store the php variable into a javascript variable
    // for this instance you can use the javascript variable v
    // in any script file if you define the variable v to be global
    var v = '<?php echo $v; ?>';
    // print it out

    // it is more readable for other user reading it
    document.write(v);
</script>

a good link also

How to embed php in javascript?

edited May 23 '17 at 11:51

Community

1
1

answered Apr 20 '15 at 03:38

Oli Soproni B.

2,774
3
22
47

An explanation of how this works or what you've fixed would boost the answer's useful tremendously. – ssube Apr 20 '15 at 04:03

score 0 · Answer 6 · answered Apr 20 '15 at 03:46

0

Try this

<input type="hidden" id="msg" value="<?php echo $v;?>">

and then call it from JS

var msg = document.getElementById('msg').value;
document.write(msg);

should work

answered Apr 20 '15 at 03:46

GaLaBoOnZ

81
4

score -1 · Answer 7 · answered Apr 20 '15 at 03:46

-1

If your goal is to see the value of the PHP variable on the web page, you could use this:

<body>
<?php $v = "random"; ?>
<p>This is the PHP variable <?php echo $v ?></p>
</body>

answered Apr 20 '15 at 03:46

user2182349

9,569
3
29
41

php variable display in js

7 Answers7