Question

197

Echo PHP inside Javascript?

rated 0 times [ 198] [ 1] / answers: 1 / hits: 86475 / 14 Years ago, tue, december 28, 2010, 12:00:00

Why is this not working?

<?php 



mysqli_select_db($connect,dev);

$response = Select response from revbut where session='$u';

$rquery  =  mysqli_query($connect,$response);



$responseanswer = mysqli_fetch_array($rquery);

$re  = $responseanswer['response'];

?>



<script type=text/javascript>

<?php echo $re; ?>

</script>

$re inside JavaScript is not getting echoed. But if I place it inside the above PHP function, it is getting echoed.

EDIT - BUT THEN WHY IS THIS NOT WORKING?

if(<?php echo $re; ?>){

    document.getElementById('hide').style.display = none;

}

if I PLACE the hide function outside the if - it is working.

Answers

Only authorized users can answer the question. Please sign in first, or register a free account.

kamryn

Add To Favorites

Follow

Total Points: 645

Total Questions: 100

Total Answers: 118

Location: Tanzania

Member since Wed, Feb 24, 2021

3 Years ago

answered 14 Years ago malkajillc · Accepted Answer

It get's echoed, but you won't see anything on your page as the text will be written within the Javascript-tag which is not displayed by the browser. Look at your page source to verify that the text is really there.

EDIT

Try

if(<?php echo json_encode($re); ?>){

    document.getElementById('hide').style.display = none; 

}

This will ensure that your PHP string will be converted into the appropriate Javascript type - in case of strings it'll ensure that the string is enclosed in and is escaped properly.

EDIT again

When you do the following

<script type=text/javascript> 

if(<?php echo $re; ?>){

    document.getElementById('hide').style.display = none; } 

</script>

this is what is written to the HTML page (that's then interpreted by the browser)

<script type=text/javascript> 

if(whatever is in the $re vairable){

    document.getElementById('hide').style.display = none; } 

</script>

But this is not even valid Javascript. What you want is

<script type=text/javascript> 

if(whatever is in the $re vairable){

    document.getElementById('hide').style.display = none; } 

</script>

Note the which ensures that the whole thing is valid Javascript and that the contents of $re will be interpreted as an Javascript string by the Browser's Javascript engine. The call to json_encode() does exactly this - it transforms PHP variables into the appropriate Javascript variables.