实体名称必须紧跟在实体引用中的“ &”之后

我想在我的 * . xhtml 页面上放一个 packman 游戏(我使用的是 jsf 2和 primefaces 3.5)

但是,

当我在 xhtml 中“翻译”html 页面时,我在这个脚本中得到一个错误:

    <script>


var el = document.getElementById("pacman");


if (Modernizr.canvas && Modernizr.localstorage &&
Modernizr.audio && (Modernizr.audio.ogg || Modernizr.audio.mp3)) {
window.setTimeout(function () { PACMAN.init(el, "./"); }, 0);
} else {
el.innerHTML = "Sorry, needs a decent browser<br /><small>" +
"(firefox 3.6+, Chrome 4+, Opera 10+ and Safari 4+)</small>";
}
</script>

排队:

if (Modernizr.canvas && Modernizr.localstorage &&

我得到了:

实体名称必须紧跟在实体中的“ &”之后 参考文献。

有办法解决吗?

244123 次浏览

You need to add a CDATA tag inside of the script tag, unless you want to manually go through and escape all XHTML characters (e.g. & would need to become &amp;). For example:

<script>
//<![CDATA[
var el = document.getElementById("pacman");


if (Modernizr.canvas && Modernizr.localstorage &&
Modernizr.audio && (Modernizr.audio.ogg || Modernizr.audio.mp3)) {
window.setTimeout(function () { PACMAN.init(el, "./"); }, 0);
} else {
el.innerHTML = "Sorry, needs a decent browser<br /><small>" +
"(firefox 3.6+, Chrome 4+, Opera 10+ and Safari 4+)</small>";
}
//]]>
</script>

The parser is expecting some HTML content, so it sees & as the beginning of an entity, like &egrave;.

Use this workaround:

<script type="text/javascript">
// <![CDATA[
Javascript code here
// ]]>
</script>

so you specify that the code is not HTML text but just data to be used as is.

Do

<script>//<![CDATA[
/* script */
//]]></script>

If you use XHTML, for some reason, note that XHTML 1.0 C 4 says: “Use external scripts if your script uses < or & or ]]> or --.” That is, don’t embed script code inside a script element but put it into a separate JavaScript file and refer to it with <script src="foo.js"></script>.

All answers posted so far are giving the right solutions, however no one answer was able to properly explain the underlying cause of the concrete problem.

Facelets is a XML based view technology which uses XHTML+XML to generate HTML output. XML has five special characters which has special treatment by the XML parser:

  • < the start of a tag.
  • > the end of a tag.
  • " the start and end of an attribute value.
  • ' the alternative start and end of an attribute value.
  • & the start of an entity (which ends with ;).

In case of & which is not followed by # (e.g. &#160;, &#xA0;, etc), the XML parser is implicitly looking for one of the five #0 lt, gt, amp, quot and apos, or any #1. However, in your particular case, you was using & as a JavaScript operator, not as an XML entity. This totally explains the XML parsing error you got:

The entity name must immediately follow the '&' in the entity reference

In essence, you're writing JavaScript code in the wrong place, a XML document instead of a JS file, so you should be escaping all XML special characters accordingly. The & must be escaped as &amp;.

So, in your particular case, the

if (Modernizr.canvas && Modernizr.localstorage &&

must become

if (Modernizr.canvas &amp;&amp; Modernizr.localstorage &amp;&amp;

to make it XML-valid.

However, this makes the JavaScript code harder to read and maintain. In case when you want to continue using & instead of &amp; in JavaScript code in a XML document, then you should be placing the JavaScript code in a character data (CDATA) block. Thus, in JSF terms, that would be:

<h:outputScript>
<![CDATA[
// ...
]]>
</h:outputScript>

The XML parser will interpret the block's contents as "plain vanilla" character data and not as XML and hence interpret the XML special characters "as-is".

But, much better is to just put the JS code in its own JS file which you include by <script src>, or in JSF terms, the <h:outputScript>.

<h:outputScript name="onload.js" target="body" />

(note the target="body"; this way JSF will automatically render the <script> at the very end of <body>, regardless of where <h:outputScript> itself is located, hereby achieving the same effect as with window.onload and $(document).ready(); so you don't need to use those anymore in that script)

This way you don't need to worry about XML-special characters in your JS code. As an additional bonus, this gives you the opportunity to let the browser cache the JS file so that total response size is smaller.

See also:

Just in case someone from Blogger arrives, I had this problem when using Beautify extension in VSCode. Don´t use it, don´t beautify it.