XDocument can't load xml with version 1.1 in C# LINQ?

Question

XDocument.Load throws exception, when using XML file name of xml with version 1.1 instead of 1.0

Any clean solutions to resolve the error (No regex) and load the document?

Answer 1

Initial reaction, just to confirm that I can reproduce this:

using System;
using System.Xml.Linq;

class Test
{   
    static void Main(string[] args)
    {
        string xml = "<?xml version=\"1.1\" ?><root><sub /></root>";
        XDocument doc = XDocument.Parse(xml);
        Console.WriteLine(doc);
    }
}

Results in this exception:

Unhandled Exception: System.Xml.XmlException: Version number '1.1' is invalid. Line 1, position 16.
   at System.Xml.XmlTextReaderImpl.Throw(Exception e)
   at System.Xml.XmlTextReaderImpl.Throw(String res, String arg)
   at System.Xml.XmlTextReaderImpl.ParseXmlDeclaration(Boolean isTextDecl)
   at System.Xml.XmlTextReaderImpl.Read()
   at System.Xml.Linq.XDocument.Load(XmlReader reader, LoadOptions options)
   at System.Xml.Linq.XDocument.Parse(String text, LoadOptions options)
   at System.Xml.Linq.XDocument.Parse(String text)
   at Test.Main(String[] args)

It fails on both .NET 3.5 and .NET 4.0 beta 1.

Answer 2

"Version 1.0" is hardcoded in various places in the standard .NET XML libraries. For example, your code seems to be falling foul of this line in System.Xml.XmlTextReaderImpl.ParseXmlDeclaration(bool):

 if (!XmlConvert.StrEqual(this.ps.chars, this.ps.charPos, charPos - this.ps.charPos, "1.0"))

I had a similar issue with XDocument.Save refusing to retain 1.1. It was the same type of thing - a hardcoded "1.0" in a System.Xml method.

I couldn't find anyway round it that still used the standard libraries.