XPathExtensions.cs

// Copyright SeaRisen LLC
// You may use this code without restrictions, but keep the copyright notice with this code.
// This file is found at: https://github.com/ChuckSavage/XmlLib
// If you find this code helpful and would like to donate, please consider purchasing one of
// the products at http://products.searisen.com, thank you.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;
using XmlLib.nXPath;

namespace XmlLib
{
    public static class XPathExtensions
    {
        /// <summary>
        /// Navigate to a specific path within source.  (create path if it doesn't exist?)
        /// <remarks>See XPath docs for help on using [number][key=value] 
        /// syntax (http://www.w3.org/TR/xpath/)</remarks>
        /// </summary>
        /// <exception cref="ArgumentOutOfRangeException" />
        public static IEnumerable<XElement> XPath(this XElement source, XPathString path, bool create)
        {
            return cXPath.Enumerable(source, path, create);
        }

        /// <summary>
        /// Navigate to a specific path within source, create it if it doesn't exist.
        /// <remarks>See XPath docs for help on using [number][key=value] 
        /// syntax (http://www.w3.org/TR/xpath/)</remarks>
        /// </summary>
        /// <exception cref="ArgumentOutOfRangeException" />
        public static IEnumerable<XElement> XPath(this XElement source, string path, params object[] args)
        {
            return XPath(source, new XPathString(path, args), false);
        }

        /// <summary>
        /// Navigate to a specific path within source.  (create path if it doesn't exist?)
        /// <remarks>See XPath docs for help on using [number][key=value] 
        /// syntax (http://www.w3.org/TR/xpath/)</remarks>
        /// </summary>
        /// <exception cref="ArgumentOutOfRangeException" />
        public static XElement XPathElement(this XElement source, XPathString path, bool create)
        {
            return XPath(source, path, create).FirstOrDefault();
        }

        /// <summary>
        /// Navigate to a specific path within source, create it if it doesn't exist.
        /// <remarks>See XPath docs for help on using [number][key=value] 
        /// syntax (http://www.w3.org/TR/xpath/)</remarks>
        /// </summary>
        /// <exception cref="ArgumentOutOfRangeException" />
        public static XElement XPathElement(this XElement source, string path, params object[] args)
        {
            return XPathElement(source, new XPathString(path, args), false);
        }

        /// <summary>
        /// Generic Get for a type.
        /// <remarks>
        /// It works as long as there is a converter for the type to convert 
        /// from string.
        /// </remarks>
        /// </summary>
        /// <returns>The elements converted to its type or the default if it 
        /// didn't exist or was empty.</returns>
        public static IEnumerable<T> XGet<T>(this XElement source, string path, T @default, params object[] args)
        {
            XPathString xp = new XPathString(path, args);
            if (xp.PathSegments.Length > 1)
            {
                XPathString last = xp.PathSegments.Last();
                if (last.Text == last.Format && 0 == last.Values.Length && !last.IsXPath)
                {
                    xp = XPathString.Combine(xp.PathSegments.Take(xp.PathSegments.Length - 1));
                    var results = XPath(source, xp, true);
                    return results.Select(x => x.Get(last.Text, @default));
                }
            }
            return XPath(source, xp, true)
                .Select(x => x.Get(null, @default));
        }

        /// <summary>
        /// Generic Get for a type.
        /// <remarks>
        /// It works as long as there is a converter for the type to convert 
        /// from string.
        /// </remarks>
        /// </summary>
        /// <returns>The element converted to its type or the default if it 
        /// didn't exist or was empty.</returns>
        public static T XGetElement<T>(this XElement source, string path, T @default, params object[] args)
        {
            var results = XGet(source, path, @default, args);
            if (results.Count() > 0)
                return results.FirstOrDefault();
            return @default;
        }
    }
}