Get the XPath to an XElement?

The extensions methods:

public static class XExtensions{    /// <summary>    /// Get the absolute XPath to a given XElement    /// (e.g. "/people/person[6]/name[1]/last[1]").    /// </summary>    public static string GetAbsoluteXPath(this XElement element)    {        if (element == null)        {            throw new ArgumentNullException("element");        }        Func<XElement, string> relativeXPath = e =>        {            int index = e.IndexPosition();            string name = e.Name.LocalName;            // If the element is the root, no index is required            return (index == -1) ? "/" + name : string.Format            (                "/{0}[{1}]",                name,                 index.ToString()            );        };        var ancestors = from e in element.Ancestors()                        select relativeXPath(e);        return string.Concat(ancestors.Reverse().ToArray()) +                relativeXPath(element);    }    /// <summary>    /// Get the index of the given XElement relative to its    /// siblings with identical names. If the given element is    /// the root, -1 is returned.    /// </summary>    /// <param name="element">    /// The element to get the index of.    /// </param>    public static int IndexPosition(this XElement element)    {        if (element == null)        {            throw new ArgumentNullException("element");        }        if (element.Parent == null)        {            return -1;        }        int i = 1; // Indexes for nodes start at 1, not 0        foreach (var sibling in element.Parent.Elements(element.Name))        {            if (sibling == element)            {                return i;            }            i++;        }        throw new InvalidOperationException            ("element has been removed from its parent.");    }}

And the test:

class Program{    static void Main(string[] args)    {        Program.Process(XDocument.Load(@"C:\test.xml").Root);        Console.Read();    }    static void Process(XElement element)    {        if (!element.HasElements)        {            Console.WriteLine(element.GetAbsoluteXPath());        }        else        {            foreach (XElement child in element.Elements())            {                Process(child);            }        }    }}

And sample output:

/tests/test[1]/date[1]/tests/test[1]/time[1]/start[1]/tests/test[1]/time[1]/end[1]/tests/test[1]/facility[1]/name[1]/tests/test[1]/facility[1]/website[1]/tests/test[1]/facility[1]/street[1]/tests/test[1]/facility[1]/state[1]/tests/test[1]/facility[1]/city[1]/tests/test[1]/facility[1]/zip[1]/tests/test[1]/facility[1]/phone[1]/tests/test[1]/info[1]/tests/test[2]/date[1]/tests/test[2]/time[1]/start[1]/tests/test[2]/time[1]/end[1]/tests/test[2]/facility[1]/name[1]/tests/test[2]/facility[1]/website[1]/tests/test[2]/facility[1]/street[1]/tests/test[2]/facility[1]/state[1]/tests/test[2]/facility[1]/city[1]/tests/test[2]/facility[1]/zip[1]/tests/test[2]/facility[1]/phone[1]/tests/test[2]/info[1]

That should settle this. No?

I updated the code by Chris to take into account namespace prefixes. Only the GetAbsoluteXPath method is modified.

public static class XExtensions{    /// <summary>    /// Get the absolute XPath to a given XElement, including the namespace.    /// (e.g. "/a:people/b:person[6]/c:name[1]/d:last[1]").    /// </summary>    public static string GetAbsoluteXPath(this XElement element)    {        if (element == null)        {            throw new ArgumentNullException("element");        }        Func<XElement, string> relativeXPath = e =>        {            int index = e.IndexPosition();            var currentNamespace = e.Name.Namespace;            string name;            if (currentNamespace == null)            {                name = e.Name.LocalName;            }            else            {                string namespacePrefix = e.GetPrefixOfNamespace(currentNamespace);                name = namespacePrefix + ":" + e.Name.LocalName;            }            // If the element is the root, no index is required            return (index == -1) ? "/" + name : string.Format            (                "/{0}[{1}]",                name,                index.ToString()            );        };        var ancestors = from e in element.Ancestors()                        select relativeXPath(e);        return string.Concat(ancestors.Reverse().ToArray()) +               relativeXPath(element);    }    /// <summary>    /// Get the index of the given XElement relative to its    /// siblings with identical names. If the given element is    /// the root, -1 is returned.    /// </summary>    /// <param name="element">    /// The element to get the index of.    /// </param>    public static int IndexPosition(this XElement element)    {        if (element == null)        {            throw new ArgumentNullException("element");        }        if (element.Parent == null)        {            return -1;        }        int i = 1; // Indexes for nodes start at 1, not 0        foreach (var sibling in element.Parent.Elements(element.Name))        {            if (sibling == element)            {                return i;            }            i++;        }        throw new InvalidOperationException            ("element has been removed from its parent.");    }}

Let me share my latest modification to this class.Basicaly it excludes index if element has no sibling and includes namespaces with local-name() operator has i was having issues with the namespace prefix.

public static class XExtensions{    /// <summary>    /// Get the absolute XPath to a given XElement, including the namespace.    /// (e.g. "/a:people/b:person[6]/c:name[1]/d:last[1]").    /// </summary>    public static string GetAbsoluteXPath(this XElement element)    {        if (element == null)        {            throw new ArgumentNullException("element");        }        Func<XElement, string> relativeXPath = e =>        {            int index = e.IndexPosition();            var currentNamespace = e.Name.Namespace;            string name;            if (String.IsNullOrEmpty(currentNamespace.ToString()))            {                name = e.Name.LocalName;            }            else            {                name = "*[local-name()='" + e.Name.LocalName + "']";                //string namespacePrefix = e.GetPrefixOfNamespace(currentNamespace);                //name = namespacePrefix + ":" + e.Name.LocalName;            }            // If the element is the root or has no sibling elements, no index is required            return ((index == -1) || (index == -2)) ? "/" + name : string.Format            (                "/{0}[{1}]",                name,                index.ToString()            );        };        var ancestors = from e in element.Ancestors()                        select relativeXPath(e);        return string.Concat(ancestors.Reverse().ToArray()) +               relativeXPath(element);    }    /// <summary>    /// Get the index of the given XElement relative to its    /// siblings with identical names. If the given element is    /// the root, -1 is returned or -2 if element has no sibling elements.    /// </summary>    /// <param name="element">    /// The element to get the index of.    /// </param>    public static int IndexPosition(this XElement element)    {        if (element == null)        {            throw new ArgumentNullException("element");        }        if (element.Parent == null)        {            // Element is root            return -1;        }        if (element.Parent.Elements(element.Name).Count() == 1)        {            // Element has no sibling elements            return -2;        }        int i = 1; // Indexes for nodes start at 1, not 0        foreach (var sibling in element.Parent.Elements(element.Name))        {            if (sibling == element)            {                return i;            }            i++;        }        throw new InvalidOperationException            ("element has been removed from its parent.");    }}