Javascript weird logical operator behavior using JSF : `&&`

Question

I am trying to work on a keydown event in javascript and I am currently stuck on something that never happened to me before :

var maxL = $("#myField").attr("maxLength")
console.log("Maximum Length : " + maxL);

if (e.key.length === 1 && str.length >= parseInt(maxL)) {
    console.log(">>>> in if");
    console.log(">>>> e.char == \"" + e.key + "\"");
    e.preventDefault();
}

When I load the page, it fails. On debug, my server console logs this error :

Error Parsing /folder/myPage.xhtml: Error Traced[line: 384] The entity name 
              must immediately follow the '&' in the entity reference.

where 384 is the line where the if is

I tried both conditions individually and they work just fine, which leads me to think there is something wrong with the "&&" operator.

If this is of any importance, I work on a WebSphere server in JSF with PrimeFaces and I try to run it in Chrome. The javascript is embedded inside a div in order to delete it after the page is loaded :

<div id="deleteScript">
    <SCRIPT>
        //my script code

        $("#deleteScript").remove();
    </SCRIPT>
</div>

looks like the jsf is interpreting parts of your js as if it was EL. Wrap your script (after the ` — Federico klez Culloca, Mar 29 '18 at 14:50
Have you checked this out? http://www-01.ibm.com/support/docview.wss?uid=swg1PI57402 — Aanand Kainth, Mar 29 '18 at 14:51
Not actually a duplicate, but same solution https://stackoverflow.com/questions/17443461/javascript-code-not-working-in-jsf-xhtml-page — Federico klez Culloca, Mar 29 '18 at 14:53
I checked again with `||` and it seems to be working, so the problem is actually related to && — Sirmyself, Mar 29 '18 at 14:54
Because your JSF code sees it and throws an error. It has no clue it is JavaScript and see an & and expects it to be & or what ever entity it is... — epascarello, Mar 29 '18 at 14:56
the `&` is reserved in come languages like XSLT. Maybe replace `&&` with `&&` or try a `CDATA[]` block — JonSG, Mar 29 '18 at 14:58

Sirmyself · Answer 1 · 2018-03-30T13:05:28.693

2

I actually had to use the following syntax :

<div id="deleteScript">
    <SCRIPT>
        <!--//--><![CDATA[//><!--
            //my script code

            $("#deleteScript").remove();
        //--><!]]>
    </SCRIPT>
</div>

Which I could find on this other answer. BalusC seems to think that we should only use this solution if we work for older web browsers, but it appears that it becomes necessary when we work on older JSF servers as well.

edited Mar 30 '18 at 13:05

answered Mar 29 '18 at 15:40

Sirmyself

1,464
1
14
29

Where have your ` – Alohci Mar 30 '18 at 02:41
Sorry, i forgot to put those! – Sirmyself Mar 30 '18 at 13:04

Federico klez Culloca · Accepted Answer · 2018-03-29T15:54:19.547

1

Looks like the jsf is interpreting parts of your js as if it was xhtml.

Wrap your script (after the <script> tag) with <![CDATA[ and ]]> to make it interpret the content literally:

<script>
    <![CDATA[
        //your code
    ]]>
</script>

The <![CDATA[ ... ]]> tags are used in XML files to allow the use of characters that usually are reserved such as '&', '>' etc. You can read more on this answer and here.

edited Mar 29 '18 at 15:54

answered Mar 29 '18 at 14:59

Federico klez Culloca

26,308
17
56
95

score 0 · Answer 3 · answered Mar 29 '18 at 14:52

0

This is not a problem with the browser; It looks like your server is attempting to operate on the "&&". Maybe you have to escape it in your code.

answered Mar 29 '18 at 14:52

Aanand Kainth

719
4
18

This would have been a better answer if it said _how_ to escape the & signs. And if it mentioned to also look for < signs. – Mr Lister Mar 29 '18 at 17:59

score -3 · Answer 4 · answered Mar 29 '18 at 14:53

-3

The problem comes from the fact that you have your JS written in the html script tag. What I would do if I were you is:

<div id="deleteScript">
    <script src="path/to/script.js"></script>
</div>

Since the script tag is within the div with ID "deleteScript", the element will exist when the script loads and you can delete it.

answered Mar 29 '18 at 14:53

TVG

259
3
8

Writing a script directly in a ` – Sirmyself Mar 29 '18 at 14:57

Javascript weird logical operator behavior using JSF : `&&`

4 Answers4