htmlcustom-attribute

Can I add a custom attribute to an HTML tag?

Can I add a custom attribute to an HTML tag like the following?

<tag myAttri="myVal" />
Solution

  • You can amend your !DOCTYPE declaration (i.e. DTD) to allow it, so that the [XML] document will still be valid:

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"
[
  <!ATTLIST tag myAttri CDATA #IMPLIED>
]>

    #IMPLIED means it is an optional attribute, or you could use #REQUIRED, etc.

    More information is in DTD - Attributes.