All XSLT documents need to be well-formed and valid XML documents, so you need to follow the same syntax rules that apply to any other XML document.
As well as ensuring that your XSLT documents are valid XML, you need to ensure they are valid XSLT documents. Here's what you need to remember when creating XSLT documents.
XSL documents are also XML documents and so we should include the XML version in the document's prolog. We should also set the
standalone attribute to
no as we now rely on an external resource (i.e. the external XSL file).
XSL Root Element
Then we open the root element —
xsl:stylesheet. The root element needs to include the XSL version as well as the XSL namespace (hence the
xsl prefix and the
XSL Namespace Prefix
All XSL elements in your XSLT document must include the