Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

external/referencesource/System.Xml/System/Xml/Cache/XPathDocumentIterator.cs

@@ -0,0 +1,271 @@
+//------------------------------------------------------------------------------
+// <copyright file="XPathDocumentIterator.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>                                                                
+// <owner current="true" primary="true">[....]</owner>
+//------------------------------------------------------------------------------
+using System;
+using System.Xml;
+using System.Xml.XPath;
+using System.Diagnostics;
+
+namespace MS.Internal.Xml.Cache {
+
+    /// <summary>
+    /// Base internal class of all XPathDocument XPathNodeIterator implementations.
+    /// </summary>
+    internal abstract class XPathDocumentBaseIterator : XPathNodeIterator {
+        protected XPathDocumentNavigator ctxt;
+        protected int pos;
+
+        /// <summary>
+        /// Create a new iterator that is initially positioned on the "ctxt" node.
+        /// </summary>
+        protected XPathDocumentBaseIterator(XPathDocumentNavigator ctxt) {
+            this.ctxt = new XPathDocumentNavigator(ctxt);
+        }
+
+        /// <summary>
+        /// Create a new iterator that is a copy of "iter".
+        /// </summary>
+        protected XPathDocumentBaseIterator(XPathDocumentBaseIterator iter) {
+            this.ctxt = new XPathDocumentNavigator(iter.ctxt);
+            this.pos = iter.pos;
+        }
+
+        /// <summary>
+        /// Return the current navigator.
+        /// </summary>
+        public override XPathNavigator Current {
+            get { return this.ctxt; }
+        }
+
+        /// <summary>
+        /// Return the iterator's current position.
+        /// </summary>
+        public override int CurrentPosition {
+            get { return this.pos; }
+        }
+    }
+
+
+    /// <summary>
+    /// Iterate over all element children with a particular QName.
+    /// </summary>
+    internal class XPathDocumentElementChildIterator : XPathDocumentBaseIterator {
+        private string localName, namespaceUri;
+
+        /// <summary>
+        /// Create an iterator that ranges over all element children of "parent" having the specified QName.
+        /// </summary>
+        public XPathDocumentElementChildIterator(XPathDocumentNavigator parent, string name, string namespaceURI) : base(parent) {
+            if (namespaceURI == null) throw new ArgumentNullException("namespaceURI");
+
+            this.localName = parent.NameTable.Get(name);
+            this.namespaceUri = namespaceURI;
+        }
+
+        /// <summary>
+        /// Create a new iterator that is a copy of "iter".
+        /// </summary>
+        public XPathDocumentElementChildIterator(XPathDocumentElementChildIterator iter) : base(iter) {
+            this.localName = iter.localName;
+            this.namespaceUri = iter.namespaceUri;
+        }
+
+        /// <summary>
+        /// Create a copy of this iterator.
+        /// </summary>
+        public override XPathNodeIterator Clone() {
+            return new XPathDocumentElementChildIterator(this);
+        }
+
+        /// <summary>
+        /// Position the iterator to the next matching child.
+        /// </summary>
+        public override bool MoveNext() {
+            if (this.pos == 0) {
+                if (!this.ctxt.MoveToChild(this.localName, this.namespaceUri))
+                    return false;
+            }
+            else {
+                if (!this.ctxt.MoveToNext(this.localName, this.namespaceUri))
+                    return false;
+            }
+
+            this.pos++;
+            return true;
+        }
+    }
+
+
+    /// <summary>
+    /// Iterate over all content children with a particular XPathNodeType.
+    /// </summary>
+    internal class XPathDocumentKindChildIterator : XPathDocumentBaseIterator {
+        private XPathNodeType typ;
+
+        /// <summary>
+        /// Create an iterator that ranges over all content children of "parent" having the specified XPathNodeType.
+        /// </summary>
+        public XPathDocumentKindChildIterator(XPathDocumentNavigator parent, XPathNodeType typ) : base(parent) {
+            this.typ = typ;
+        }
+
+        /// <summary>
+        /// Create a new iterator that is a copy of "iter".
+        /// </summary>
+        public XPathDocumentKindChildIterator(XPathDocumentKindChildIterator iter) : base(iter) {
+            this.typ = iter.typ;
+        }
+
+        /// <summary>
+        /// Create a copy of this iterator.
+        /// </summary>
+        public override XPathNodeIterator Clone() {
+            return new XPathDocumentKindChildIterator(this);
+        }
+
+        /// <summary>
+        /// Position the iterator to the next descendant.
+        /// </summary>
+        public override bool MoveNext() {
+            if (this.pos == 0) {
+                if (!this.ctxt.MoveToChild(this.typ))
+                    return false;
+            }
+            else {
+                if (!this.ctxt.MoveToNext(this.typ))
+                    return false;
+            }
+
+            this.pos++;
+            return true;
+        }
+    }
+
+
+    /// <summary>
+    /// Iterate over all element descendants with a particular QName.
+    /// </summary>
+    internal class XPathDocumentElementDescendantIterator : XPathDocumentBaseIterator {
+        private XPathDocumentNavigator end;
+        private string localName, namespaceUri;
+        private bool matchSelf;
+
+        /// <summary>
+        /// Create an iterator that ranges over all element descendants of "root" having the specified QName.
+        /// </summary>
+        public XPathDocumentElementDescendantIterator(XPathDocumentNavigator root, string name, string namespaceURI, bool matchSelf) : base(root) {
+            if (namespaceURI == null) throw new ArgumentNullException("namespaceURI");
+
+            this.localName = root.NameTable.Get(name);
+            this.namespaceUri = namespaceURI;
+            this.matchSelf = matchSelf;
+
+            // Find the next non-descendant node that follows "root" in document order
+            if (root.NodeType != XPathNodeType.Root) {
+                this.end = new XPathDocumentNavigator(root);
+                this.end.MoveToNonDescendant();
+            }
+        }
+
+        /// <summary>
+        /// Create a new iterator that is a copy of "iter".
+        /// </summary>
+        public XPathDocumentElementDescendantIterator(XPathDocumentElementDescendantIterator iter) : base(iter) {
+            this.end = iter.end;
+            this.localName = iter.localName;
+            this.namespaceUri = iter.namespaceUri;
+            this.matchSelf = iter.matchSelf;
+        }
+
+        /// <summary>
+        /// Create a copy of this iterator.
+        /// </summary>
+        public override XPathNodeIterator Clone() {
+            return new XPathDocumentElementDescendantIterator(this);
+        }
+
+        /// <summary>
+        /// Position the iterator to the next descendant.
+        /// </summary>
+        public override bool MoveNext() {
+            if (this.matchSelf) {
+                this.matchSelf = false;
+
+                if (this.ctxt.IsElementMatch(this.localName, this.namespaceUri)) {
+                    this.pos++;
+                    return true;
+                }
+            }
+
+            if (!this.ctxt.MoveToFollowing(this.localName, this.namespaceUri, this.end))
+                return false;
+
+            this.pos++;
+            return true;
+        }
+    }
+
+
+    /// <summary>
+    /// Iterate over all content descendants with a particular XPathNodeType.
+    /// </summary>
+    internal class XPathDocumentKindDescendantIterator : XPathDocumentBaseIterator {
+        private XPathDocumentNavigator end;
+        private XPathNodeType typ;
+        private bool matchSelf;
+
+        /// <summary>
+        /// Create an iterator that ranges over all content descendants of "root" having the specified XPathNodeType.
+        /// </summary>
+        public XPathDocumentKindDescendantIterator(XPathDocumentNavigator root, XPathNodeType typ, bool matchSelf) : base(root) {
+            this.typ = typ;
+            this.matchSelf = matchSelf;
+
+            // Find the next non-descendant node that follows "root" in document order
+            if (root.NodeType != XPathNodeType.Root) {
+                this.end = new XPathDocumentNavigator(root);
+                this.end.MoveToNonDescendant();
+            }
+        }
+
+        /// <summary>
+        /// Create a new iterator that is a copy of "iter".
+        /// </summary>
+        public XPathDocumentKindDescendantIterator(XPathDocumentKindDescendantIterator iter) : base(iter) {
+            this.end = iter.end;
+            this.typ = iter.typ;
+            this.matchSelf = iter.matchSelf;
+        }
+
+        /// <summary>
+        /// Create a copy of this iterator.
+        /// </summary>
+        public override XPathNodeIterator Clone() {
+            return new XPathDocumentKindDescendantIterator(this);
+        }
+
+        /// <summary>
+        /// Position the iterator to the next descendant.
+        /// </summary>
+        public override bool MoveNext() {
+            if (this.matchSelf) {
+                this.matchSelf = false;
+
+                if (this.ctxt.IsKindMatch(this.typ)) {
+                    this.pos++;
+                    return true;
+                }
+            }
+
+            if (!this.ctxt.MoveToFollowing(this.typ, this.end))
+                return false;
+
+            this.pos++;
+            return true;
+        }
+    }
+}
+