XHTML won't validate && and < in a JavaScript function

问题

Here's the snippet of code that won't validate:

if (user_age > 15 && user_age < 91)

It gets the following errors:

XML Parsing Error: StartTag: invalid element name

and

XML Parsing Error: xmlParseEntityRef: no name

The first error is thrown for the "less than" and the second one is thrown twice, once for each ampersand.

Replacing the above signs with & and < validates fine, but of course it completely ruins the function.

回答1:

Or you can protect the script from the xml validation like this:

<script type="text/javascript"> 
//<![CDATA[
    if (user_age > 15 && user_age < 91) {
        // do soemthing
    }
//]]>
</script> 

回答2:

Move script to other file :)

It is standard (and good) habit to separate style (into .css file), data (.html) and of course scripts to .js file.

回答3:

All Javascript should be CDATA in XHTML:

<![CDATA[
if (user_age > 15 && user_age < 91)
]]>

回答4:

put javascript in <![CDATA[...]]> section

回答5:

you can try CDATA but some time it wont work, it depends on the setting of the server I guess. I am not a pro, but i tested, and I did not work, but if you put the javascript code in the .js file and then link this file somewhere in your body. it will definitely work. PERSONALLY TESTED.

来源：https://stackoverflow.com/questions/1513871/xhtml-wont-validate-and-in-a-javascript-function