mcs/class/referencesource/System.Xml/System/Xml/XPath/Internal/ParentQuery.cs

   1 //------------------------------------------------------------------------------
   2 // <copyright file="ParentQuery.cs" company="Microsoft">
   3 //     Copyright (c) Microsoft Corporation.  All rights reserved.
   4 // </copyright>
   5 // <owner current="true" primary="true">Microsoft</owner>
   6 //------------------------------------------------------------------------------
   7
   8 namespace MS.Internal.Xml.XPath {
   9     using System;
  10     using System.Xml;
  11     using System.Xml.XPath;
  12     using System.Diagnostics;
  13     using System.Globalization;
  14     using System.Collections.Generic;
  15
  16     internal sealed class ParentQuery : CacheAxisQuery {
  17
  18         public ParentQuery(Query  qyInput, string Name, string Prefix, XPathNodeType Type) : base(qyInput, Name, Prefix, Type) {}
  19         private ParentQuery(ParentQuery other) : base(other) { }
  20
  21         public override object Evaluate(XPathNodeIterator context) {
  22             base.Evaluate(context);
  23
  24             //
  25             XPathNavigator input;
  26             while ((input = qyInput.Advance()) != null) {
  27                 input = input.Clone();
  28
  29                 if (input.MoveToParent()) {
  30                     if (matches(input)) {
  31                         Insert(outputBuffer, input);
  32                     }
  33                 }
  34             }
  35             return this;
  36         }
  37
  38         public override XPathNodeIterator Clone() { return new ParentQuery(this); }
  39     }
  40 }