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

   1 //
   2 // XmlNamespaceManager.cs
   3 //
   4 // Author:
   5 //   Jason Diamond (jason@injektilo.org)
   6 //
   7 // (C) 2001 Jason Diamond  http://injektilo.org/
   8 //
   9
  10 using System.Collections;
  11
  12 namespace System.Xml
  13 {
  14         public class XmlNamespaceManager : IEnumerable
  15         {
  16                 #region Fields
  17
  18                 private XmlNameTable nameTable;
  19                 private NamespaceScope currentScope;
  20
  21                 #endregion
  22
  23                 #region Constructor
  24
  25                 public XmlNamespaceManager (XmlNameTable nameTable)
  26                 {
  27                         this.nameTable = nameTable;
  28
  29                         nameTable.Add ("xmlns");
  30                         nameTable.Add ("xml");
  31                         nameTable.Add (String.Empty);
  32                         nameTable.Add ("http://www.w3.org/2000/xmlns/");
  33                         nameTable.Add ("http://www.w3.org/XML/1998/namespace");
  34
  35                         PushScope ();
  36                 }
  37
  38                 #endregion
  39
  40                 #region Properties
  41
  42                 public virtual string DefaultNamespace {
  43                         get { return LookupNamespace (String.Empty); }
  44                 }
  45
  46                 public XmlNameTable NameTable {
  47                         get { return nameTable; }
  48                 }
  49
  50                 #endregion
  51
  52                 #region Methods
  53
  54                 public virtual void AddNamespace (string prefix, string uri)
  55                 {
  56                         if (prefix == null)
  57                                 throw new ArgumentNullException ("prefix", "Value cannot be null.");
  58
  59                         if (uri == null)
  60                                 throw new ArgumentNullException ("uri", "Value cannot be null.");
  61
  62                         if (prefix.Length > 2 && prefix.Substring (0, 3).ToLower () == "xml")
  63                                 throw new ArgumentException ("Prefixes beginning with \"xml\" (regardless of whether the characters are uppercase, lowercase, or some combination thereof) are reserved for use by XML.", "prefix");
  64
  65                         if (currentScope.Namespaces == null)
  66                                 currentScope.Namespaces = new Hashtable ();
  67
  68                         if (prefix == String.Empty)
  69                                 currentScope.Namespaces [prefix] = nameTable.Add (uri);
  70                         else
  71                                 currentScope.Namespaces.Add (nameTable.Add (prefix), nameTable.Add (uri));
  72                 }
  73
  74                 [MonoTODO]
  75                 public virtual IEnumerator GetEnumerator ()
  76                 {
  77                         throw new NotImplementedException ();
  78                 }
  79
  80                 public virtual bool HasNamespace (string prefix)
  81                 {
  82                         return currentScope != null && currentScope.Namespaces != null && currentScope.Namespaces.Contains (prefix);
  83                 }
  84
  85                 public virtual string LookupNamespace (string prefix)
  86                 {
  87                         NamespaceScope scope = currentScope;
  88
  89                         while (scope != null) {
  90                                 if (scope.Namespaces != null && scope.Namespaces.Contains (prefix))
  91                                         return scope.Namespaces[prefix] as string;
  92                                 scope = scope.Next;
  93                         }
  94
  95                         switch (prefix) {
  96                         case "xmlns":
  97                                 return nameTable.Get ("http://www.w3.org/2000/xmlns/");
  98                         case "xml":
  99                                 return nameTable.Get ("http://www.w3.org/XML/1998/namespace");
 100                         case "":
 101                                 return nameTable.Get (String.Empty);
 102                         }
 103
 104                         return null;
 105                 }
 106
 107                 public virtual string LookupPrefix (string uri)
 108                 {
 109                         if (uri == null)
 110                                 return null;
 111
 112                         NamespaceScope scope = currentScope;
 113
 114                         while (scope != null)
 115                         {
 116                                 if (scope.Namespaces != null && scope.Namespaces.ContainsValue (uri)) {
 117                                         foreach (DictionaryEntry entry in scope.Namespaces) {
 118                                                 if (entry.Value.ToString() == uri)
 119                                                         return nameTable.Get (entry.Key as string) as string;
 120                                         }
 121                                 }
 122
 123                                 scope = scope.Next;
 124                         }
 125
 126                         return String.Empty;
 127                 }
 128
 129                 public virtual bool PopScope ()
 130                 {
 131                         if (currentScope != null)
 132                                 currentScope = currentScope.Next;
 133
 134                         return currentScope != null;
 135                 }
 136
 137                 public virtual void PushScope ()
 138                 {
 139                         NamespaceScope newScope = new NamespaceScope ();
 140                         newScope.Next = currentScope;
 141                         currentScope = newScope;
 142                 }
 143
 144                 [MonoTODO]
 145                 public virtual void RemoveNamespace (string prefix, string uri)
 146                 {
 147                         throw new NotImplementedException ();
 148                 }
 149
 150                 #endregion
 151         }
 152
 153         internal class NamespaceScope
 154         {
 155                 internal NamespaceScope Next;
 156                 internal Hashtable Namespaces;
 157         }
 158 }