mcs/class/System.Xml.Linq/System.Xml.XPath/Extensions.cs

   1 //
   2 // Authors:
   3 //   Atsushi Enomoto
   4 //
   5 // Copyright 2007 Novell (http://www.novell.com)
   6 //
   7 // Permission is hereby granted, free of charge, to any person obtaining
   8 // a copy of this software and associated documentation files (the
   9 // "Software"), to deal in the Software without restriction, including
  10 // without limitation the rights to use, copy, modify, merge, publish,
  11 // distribute, sublicense, and/or sell copies of the Software, and to
  12 // permit persons to whom the Software is furnished to do so, subject to
  13 // the following conditions:
  14 //
  15 // The above copyright notice and this permission notice shall be
  16 // included in all copies or substantial portions of the Software.
  17 //
  18 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  21 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  22 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25 //
  26
  27 #if !MOONLIGHT
  28
  29 using System;
  30 using System.Collections;
  31 using System.Collections.Generic;
  32 using System.Xml;
  33 using System.Xml.Linq;
  34
  35 namespace System.Xml.XPath
  36 {
  37         public static class Extensions
  38         {
  39                 public static XPathNavigator CreateNavigator (this XNode node)
  40                 {
  41                         return CreateNavigator (node, new NameTable ());
  42                 }
  43
  44                 public static XPathNavigator CreateNavigator (this XNode node, XmlNameTable nameTable)
  45                 {
  46                         return new XNodeNavigator (node, nameTable);
  47                 }
  48
  49                 public static object XPathEvaluate (this XNode node, string expression)
  50                 {
  51                         return XPathEvaluate (node, expression, null);
  52                 }
  53
  54                 public static object XPathEvaluate (this XNode node, string expression, IXmlNamespaceResolver nsResolver)
  55                 {
  56                         object navigationResult = CreateNavigator (node).Evaluate (expression, nsResolver);
  57                         if (!(navigationResult is XPathNodeIterator))
  58                                 return navigationResult;
  59                         return GetUnderlyingXObjects((XPathNodeIterator) navigationResult);
  60                 }
  61
  62                 private static IEnumerable<XObject> GetUnderlyingXObjects(XPathNodeIterator nodeIterator)
  63                 {
  64                         foreach (XPathNavigator nav in nodeIterator)
  65                         {
  66                                 yield return (XObject)(nav.UnderlyingObject);
  67                         }
  68                 }
  69
  70                 public static XElement XPathSelectElement (this XNode node, string xpath)
  71                 {
  72                         return XPathSelectElement (node, xpath, null);
  73                 }
  74
  75                 public static XElement XPathSelectElement (this XNode node, string xpath, IXmlNamespaceResolver nsResolver)
  76                 {
  77                         XPathNavigator nav = CreateNavigator (node).SelectSingleNode (xpath, nsResolver);
  78                         if (nav == null)
  79                                 return null;
  80                         return nav.UnderlyingObject as XElement;
  81                 }
  82
  83                 public static IEnumerable<XElement> XPathSelectElements (this XNode node, string xpath)
  84                 {
  85                         return XPathSelectElements (node, xpath, null);
  86                 }
  87
  88                 public static IEnumerable<XElement> XPathSelectElements (this XNode node, string xpath, IXmlNamespaceResolver nsResolver)
  89                 {
  90                         XPathNodeIterator iter = CreateNavigator (node).Select (xpath, nsResolver);
  91                         foreach (XPathNavigator nav in iter){
  92                                 if (nav.UnderlyingObject is XElement)
  93                                         yield return (XElement) nav.UnderlyingObject;
  94                         }
  95                 }
  96         }
  97 }
  98
  99 #endif