mcs/class/System.XML/System.Xml/XmlAttribute.cs

   1 //
   2 // System.Xml.XmlAttribute
   3 //
   4 // Authors:
   5 //   Jason Diamond (jason@injektilo.org)
   6 //   Atsushi Enomoto (ginga@kit.hi-ho.ne.jp)
   7 //
   8 // (C) 2002 Jason Diamond  http://injektilo.org/
   9 // (C) 2003 Atsushi Enomoto
  10 //
  11
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System;
  34 using System.Text;
  35 using System.Xml.XPath;
  36 using Mono.Xml;
  37
  38 namespace System.Xml
  39 {
  40         public class XmlAttribute : XmlNode
  41         {
  42                 #region Fields
  43
  44                 private string localName;
  45                 private string namespaceURI;
  46                 private string prefix;
  47                 internal bool isDefault;
  48                 private XmlElement ownerElement;
  49
  50                 #endregion
  51
  52                 #region Constructor
  53
  54                 protected internal XmlAttribute (
  55                         string prefix,
  56                         string localName,
  57                         string namespaceURI,
  58                         XmlDocument doc) : this (prefix, localName, namespaceURI, doc, false, true)
  59                 {
  60                 }
  61
  62                 internal XmlAttribute (
  63                         string prefix,
  64                         string localName,
  65                         string namespaceURI,
  66                         XmlDocument doc,
  67                         bool atomizedNames, bool checkNamespace) : base (doc)
  68                 {
  69                         if (prefix == null)
  70                                 prefix = String.Empty;
  71                         if (namespaceURI == null)
  72                                 namespaceURI = String.Empty;
  73
  74                         // Prefix "xml" should be also checked (http://www.w3.org/XML/xml-names-19990114-errata#NE05)
  75                         // but MS.NET ignores such case
  76                         if (checkNamespace) {
  77                                 if (prefix == "xmlns" || (prefix == "" && localName == "xmlns"))
  78                                         if (namespaceURI != XmlNamespaceManager.XmlnsXmlns)
  79                                                 throw new ArgumentException ("Invalid attribute namespace for namespace declaration.");
  80                                 else if (prefix == "xml" && namespaceURI != XmlNamespaceManager.XmlnsXml)
  81                                         throw new ArgumentException ("Invalid attribute namespace for namespace declaration.");
  82                         }
  83
  84                         // There are no means to identify the DOM is namespace-
  85                         // aware or not, so we can only check Name validity.
  86                         if (prefix != "" && !XmlChar.IsName (prefix))
  87                                 throw new ArgumentException ("Invalid attribute prefix.");
  88                         else if (!XmlChar.IsName (localName))
  89                                 throw new ArgumentException ("Invalid attribute local name.");
  90
  91                         if (atomizedNames) {
  92                                 this.prefix = prefix;
  93                                 this.localName = localName;
  94                                 this.namespaceURI = namespaceURI;
  95                         } else {
  96                                 this.prefix = doc.NameTable.Add (prefix);
  97                                 this.localName = doc.NameTable.Add (localName);
  98                                 this.namespaceURI = doc.NameTable.Add (namespaceURI);
  99                         }
 100                 }
 101
 102                 #endregion
 103
 104                 #region Properties
 105
 106                 public override string BaseURI {
 107                         get { return OwnerElement != null ? OwnerElement.BaseURI : String.Empty; }
 108                 }
 109
 110                 public override string InnerText {
 111                         get {
 112                                 return base.InnerText;
 113                         }
 114
 115                         set {
 116                                 Value = value;
 117                         }
 118                 }
 119
 120                 public override string InnerXml {
 121                         get {
 122                                 // Not sure why this is an override.  Passing through for now.
 123                                 return base.InnerXml;
 124                         }
 125
 126                         set {
 127                                 RemoveAll ();
 128                                 XmlNamespaceManager nsmgr = ConstructNamespaceManager ();
 129                                 XmlParserContext ctx = new XmlParserContext (OwnerDocument.NameTable, nsmgr,
 130                                         OwnerDocument.DocumentType != null ? OwnerDocument.DocumentType.DTD : null,
 131                                         BaseURI, XmlLang, XmlSpace, null);
 132                                 XmlTextReader xtr = new XmlTextReader (value, XmlNodeType.Attribute, ctx);
 133                                 xtr.XmlResolver = OwnerDocument.Resolver;
 134                                 xtr.Read ();
 135                                 OwnerDocument.ReadAttributeNodeValue (xtr, this);
 136                         }
 137                 }
 138
 139                 public override string LocalName {
 140                         get {
 141                                 return localName;
 142                         }
 143                 }
 144
 145                 public override string Name {
 146                         get {
 147                                 return prefix != String.Empty ? OwnerDocument.NameTable.Add (prefix + ":" + localName) : localName;
 148                         }
 149                 }
 150
 151                 public override string NamespaceURI {
 152                         get {
 153                                 return namespaceURI;
 154                         }
 155                 }
 156
 157                 public override XmlNodeType NodeType {
 158                         get {
 159                                 return XmlNodeType.Attribute;
 160                         }
 161                 }
 162
 163                 internal override XPathNodeType XPathNodeType {
 164                         get {
 165                                 return XPathNodeType.Attribute;
 166                         }
 167                 }
 168
 169                 public override XmlDocument OwnerDocument {
 170                         get {
 171                                 return base.OwnerDocument;
 172                         }
 173                 }
 174
 175                 public virtual XmlElement OwnerElement {
 176                         get { return ownerElement; }
 177                 }
 178
 179                 public override XmlNode ParentNode {
 180                         get {
 181                                 // It always returns null (by specification).
 182                                 return null;
 183                         }
 184                 }
 185
 186                 // We gotta do more in the set block here
 187                 // We need to do the proper tests and throw
 188                 // the correct Exceptions
 189                 //
 190                 // Wrong cases are: (1)check readonly, (2)check character validity,
 191                 // (3)check format validity, (4)this is attribute and qualifiedName != "xmlns"
 192                 public override string Prefix {
 193                         set {
 194                                 if (IsReadOnly)
 195                                         throw new XmlException ("This node is readonly.");
 196                                 if (!XmlChar.IsNCName (value))
 197                                         throw new ArgumentException ("Specified name is not a valid NCName: " + value);
 198                                 if (prefix == "xmlns" && value != "xmlns")
 199                                         throw new ArgumentException ("Cannot bind to the reserved namespace.");
 200
 201                                 prefix = OwnerDocument.NameTable.Add (value);
 202                         }
 203
 204                         get {
 205                                 return prefix;
 206                         }
 207                 }
 208
 209                 public virtual bool Specified {
 210                         get {
 211                                 return !isDefault;
 212                         }
 213                 }
 214
 215                 private string BuildChildValue (XmlNodeList list)
 216                 {
 217                         string ret = String.Empty;
 218                         for (int i = 0; i < list.Count; i++) {
 219                                 if (list [i].NodeType == XmlNodeType.EntityReference)
 220                                         ret += BuildChildValue (list [i].ChildNodes);
 221                                 else
 222                                         ret += list [i].Value;
 223                         }
 224                         return ret;
 225                 }
 226
 227                 public override string Value {
 228                         get { return BuildChildValue (ChildNodes); }
 229
 230                         set {
 231                                 if (this.IsReadOnly)
 232                                         throw new ArgumentException ("Attempt to modify a read-only node.");
 233                                 XmlNode firstChild = FirstChild;
 234                                 if (firstChild == null)
 235                                         AppendChild (OwnerDocument.CreateTextNode (value));
 236                                 else if (FirstChild.NextSibling != null) {
 237                                         this.RemoveAll ();
 238                                         AppendChild (OwnerDocument.CreateTextNode (value));
 239                                 }
 240                                 else
 241                                         firstChild.Value = value;
 242                                 isDefault = false;
 243                         }
 244                 }
 245
 246                 internal override string XmlLang {
 247                         get { return OwnerElement != null ? OwnerElement.XmlLang : String.Empty; }
 248                 }
 249
 250                 internal override XmlSpace XmlSpace {
 251                         get { return OwnerElement != null ? OwnerElement.XmlSpace : XmlSpace.None; }
 252                 }
 253
 254                 #endregion
 255
 256                 #region Methods
 257
 258                 public override XmlNode CloneNode (bool deep)
 259                 {
 260                         XmlNode node = new XmlAttribute (prefix, localName, namespaceURI,
 261                                                          OwnerDocument, true, false);
 262                         if (deep) {
 263                                 for (int i = 0; i < ChildNodes.Count; i++)
 264                                         node.AppendChild (ChildNodes [i].CloneNode (deep));
 265                         }
 266
 267                         if (IsReadOnly)
 268                                 node.SetReadOnly ();
 269                         return node;
 270                 }
 271
 272                 internal void SetDefault ()
 273                 {
 274                         isDefault = true;
 275                 }
 276
 277                 // Parent of XmlAttribute must be null
 278                 internal void SetOwnerElement (XmlElement el) {
 279                         ownerElement = el;
 280                 }
 281
 282                 public override void WriteContentTo (XmlWriter w)
 283                 {
 284                         for (int i = 0; i < ChildNodes.Count; i++)
 285                                 ChildNodes [i].WriteTo (w);
 286                 }
 287
 288                 public override void WriteTo (XmlWriter w)
 289                 {
 290                         w.WriteStartAttribute (prefix, localName, namespaceURI);
 291                         WriteContentTo (w);
 292                         w.WriteEndAttribute ();
 293                 }
 294
 295                 internal DTDAttributeDefinition GetAttributeDefinition ()
 296                 {
 297                         if (OwnerElement == null)
 298                                 return null;
 299
 300                         // If it is default, then directly create new attribute.
 301                         DTDAttListDeclaration attList = OwnerDocument.DocumentType != null ? OwnerDocument.DocumentType.DTD.AttListDecls [OwnerElement.Name] : null;
 302                         return attList != null ? attList [Name] : null;
 303                 }
 304                 #endregion
 305         }
 306 }