What use is the ‘encoding’ in the XML header?

by

As you mentioned, you’d have to know the encoding of the file to read the encoding attribute.

However, there is a heuristic that can easily get you close enough to the “real” encoding to allow you to read the encoding attribute. This works, because the <?xml part by definition can only contain characters in the ASCII range (however they are encoded).

The XML standard even describes the exact process used to find out the encoding.

And the encoding label isn’t redundant either. For example, if you use the algorithm in the XML spec to find out that some ASCII-based (or ASCII-compatible) encoding is used you still need to read the encoding to find out which one is actually use (valid candidates would be ASCII, UTF-8, any of the ISO-8859-* encodings, any of the Windows-* encodings, KOI8-R and many, many others). For the <?xml part itself it won’t make a difference which one it is, but for the rest of the document, it can make a huge difference.

Regarding mis-labeled XML files: yes, it’s easy to produce those, however: the XML spec clearly specifies that those files are mal-formed and as such are not correct XML. Incorrect encodings must be reported as an error (as long as they can be detected!). So it’s the problem of whoever is producing the XML.

More Related Contents:

  1. Meaning of –
  2. Does any xml-based standard exist to define HTTP requests and responses as xml files?
  3. How to fix error: The markup in the document following the root element must be well-formed
  4. Does a valid XML file require an XML declaration?
  5. Are SVG parameters such as ‘xmlns’ and ‘version’ needed?
  6. Any tools to generate an XSD schema from an XML instance document? [closed]
  7. XPath select all elements between two specific elements
  8. javax.xml.bind.JAXBException Implementation of JAXB-API has not been found on module path or classpath
  9. Extraction of data from a simple XML file
  10. How to use XPath contains() here?
  11. Is writing self closing tags for elements not traditionally empty bad practice?
  12. How to properly assemble a valid xlsx file from its internal sub-components?
  13. How to restrict the value of an XML element using xsi:type in XSD?
  14. Convert a Nokogiri document to a Ruby Hash
  15. XML Schema (XSD) validation tool? [closed]
  16. How to declare XPath namespaces in xmlstarlet?
  17. R: convert XML data to data frame
  18. What is the XPath to select a range of nodes?
  19. Incrementing and checking the counter variable in XSLT
  20. Date operations on xsl 1.0
  21. How to parse xml in Angular 2
  22. What is the difference between root node, root element and document element in XML?
  23. How to remove namespaces from XML using XSLT
  24. How to link up XML file with XSLT file?
  25. Need help in creating XSLT, i do have Source and Target XML
  26. Creating hashmap/map from XML resources
  27. Scala – modifying nested elements in xml
  28. XSLT Transform XML with Namespaces
  29. How to create xml from R objects, e.g., is there a ‘listToXml’ function?
  30. Powershell script to update XML file content

Leave a Comment