passing special characters to javascript function

Question

I have the following code: opener.postConditionPostCure("<?php echo the_field('cure_description'); ?>")

In some cases the_field() returns ' " ) characters. I believe these characters are throwing errors. I have tried using the js fn escape() function as well as the php fn rawurlencode() as:

opener.postConditionPostCure(escape("<?php echo the_field('cure_description'); ?>"))
opener.postConditionPostCure("<?php echo rawurlencode(the_field('cure_description')); ?>")

to no avail.

I would like the entire string returned by the_field() to be passed to the postConditionPostCure function.

All advice is appreciated. Thanks in advance.

Encode it as JSON. [Pass a PHP string to a JavaScript variable (and escape newlines)](http://stackoverflow.com/questions/168214/pass-a-php-string-to-a-javascript-variable-and-escape-newlines) — Jonathan Lonowski, Oct 12 '14 at 04:58
Why are you [asking the same question](http://stackoverflow.com/questions/25793124/how-to-deal-with-illegal-characters-in-javascript-function-parameters) again ? — Mulan, Oct 12 '14 at 05:46

score 1 · Answer 1 · answered Oct 12 '14 at 04:55

1

Use the PHP function addslashes() which will escape those characters that are causing chaos in js.

opener.postConditionPostCure("<?php echo addslashes(the_field('cure_description')); ?>")

answered Oct 12 '14 at 04:55

brian

2,745
2
17
33

It has to work, that's what that function does. Can you paste what your script renders? – brian Oct 12 '14 at 05:05
opener.postConditionPostCure("text:
– bob Oct 12 '14 at 05:13
Where is the `")`? That's part of the JS, it should already be there. – brian Oct 12 '14 at 05:15
I think it is erroring out by the >, sorry, I should have included that symbol as well. – bob Oct 12 '14 at 13:03

score 1 · Accepted Answer · edited Apr 12 '17 at 07:31

This is horrible.

Never ever, ever, ever integrate dynamic output directly into javascript like that.

Read the plethora of reasons why this is a terrible practice here.

But since you're just going to do it anyway, at least encode the JavaScript value properly first.

var json = '<?php echo json_encode(the_field("cure_description"), JSON_HEX_APOS) ?>';

var cureDescription = JSON.parse(json);

opener.postConditionPostCure(cureDescription);

I'm calling json_encode with the JSON_HEX_APOS flag because I'm wrapping the JSON in ' (single quotes) in the JavaScript.

You have two other more ideal options at your disposal though

use ajax to get the value you need
render a <input type="hidden"> and fetch the value using JavaScript.

Both solutions avoid embedding PHP directly in your JS.

Hello, thanks for the answer. It is really helpful. Ill work on it now and see what I come up with — bob, Oct 12 '14 at 13:09
@bob no problem. If you have other questions, I'll be happy to help. — Mulan, Oct 12 '14 at 15:36

passing special characters to javascript function

2 Answers2