invalid token XPath expression

[Whileoflife]

When I run the code below I get the error: has an invalid token

Any suggestions?

<?xml version="1.0"?>
<root>
<Japan>ユーザーおよび管理者</Japan>
<English>'Guest' and "Administrator"</English>
</root>
<root>
<Japan>........</Japan>
<English>.............</English>
</root>

Here is my code:

// Create an XPathExpression
string strEnglish = "'Guest' and \"Administrator\"";
xPathExpr = nav.Compile( string.Format( "//root[English={0}\"]/Japan", strEnglish) ); 

[nukefusion]

Hi and welcome to the forums,

First of all, your XML document is technically invalid as it doesn't have a single root element. With the samples you've posted your current code will more than likely fail with a runtime exception stating that. So first you need to add a root element that encompasses all others.

The problem with your XPath here is that you have both single and double quotes in the element value. There's a trick you can use to get around this using the XPath concat function, you break up the string into sections using only one type of quote and join them like so:

string strEnglish = "concat(\"'Guest' and \", '\"Administrator\"')";
 

Providing you add a proper root element to your XML document, this should locate the node you're looking for.

In the future however, if you have any control over the XML document you might want to consider looking into the escape codes ' and " instead. Could save you some hassle.

Hope this helps.

[Whileoflife]

Thanks nukefusion,
I have function to generate concat for XPath:

private string GenerateConcatForXPath( string a_xPathQueryString )
        {
            string returnString = string.Empty;
            string searchString = a_xPathQueryString;
            char[] quoteChars = new char[] { '\'', '"' };
            int quotePos = searchString.IndexOfAny( quoteChars );
            if ( quotePos == -1 )
            {
                returnString = "'" + searchString + "'";
            }
            else
            {
                returnString = "concat(";
                while ( quotePos != -1 )
                {
                    string subString = searchString.Substring( 0, quotePos );
                    returnString += "'" + subString + "', ";
                    if ( searchString.Substring( quotePos, 1 ) == "'" )
                    {
                        returnString += "\"'\", ";
                    }
                    else
                    {
                        //must be a double quote
                        returnString += "'\"', ";
                    }
                    searchString = searchString.Substring( quotePos + 1,
                                     searchString.Length - quotePos - 1 );
                    quotePos = searchString.IndexOfAny( quoteChars );
                }
                returnString += "'" + searchString + "')";
            }
            return returnString;
        }

To use:

// Create an XPathExpression 
string strEnglish = GenerateConcatForXPath("'Guest' and \"Administrator\""); 
xPathExpr = nav.Compile( string.Format( "//root[English={0}\"]/Japan", strEnglish) );