We get W3C validation error after placing Scheme Data in our website which was built in XHTML.Line 198, Column 41: there is no attribute data-id<script type=IN/FollowCompany data-id=322498 data-counter=right></script>(Link to the validator result)Will changing the DTD solve this? We use,<!DOCTYPE html PUBLIC -//W3C//DTD XHTML 1.0 Transitional//EN http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd>
What is the correct DTD for Schema DATA placement in XHTML pages?
microdata;xhtml;w3c validation
The data-* attributes are defined for (X)HTML5 only.The Microdata attributes (itemscope, itemprop, ) are defined for (X)HTML5 only.So when you switch to (X)HTML5, you can use both of these. If you want to keep using XHTML 1.0, you could use class instead of data-* attributes, and RDFa instead of Microdata (which requires adjusting your DOCTYPE).