class/System.XML/System.Xml/XmlUrlResolver.cs

   1 // System.Xml.XmlUrlResolver.cs
   2 //
   3 // Author: Duncan Mak (duncan@ximian.com)
   4 //         Atsushi Enomoto (ginga@kit.hi-ho.ne.jp)
   5 //
   6 // (C) Ximian, Inc.
   7 //
   8
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System.Net;
  31 using System.IO;
  32 using System.Text;
  33
  34 namespace System.Xml
  35 {
  36         public class XmlUrlResolver : XmlResolver
  37         {
  38                 // Field
  39                 ICredentials credential;
  40
  41                 // Constructor
  42                 public XmlUrlResolver ()
  43                         : base ()
  44                 {
  45                 }
  46
  47                 // Properties
  48                 public override ICredentials Credentials
  49                 {
  50                         set { credential = value; }
  51                 }
  52
  53                 // Methods
  54                 public override object GetEntity (Uri absoluteUri, string role, Type ofObjectToReturn)
  55                 {
  56                         if (ofObjectToReturn == null)
  57                                 ofObjectToReturn = typeof (Stream);
  58                         if (ofObjectToReturn != typeof (Stream))
  59                                 throw new XmlException ("This object type is not supported.");
  60
  61 #if NET_2_0
  62                         if (!absoluteUri.IsAbsoluteUri)
  63                                 throw new ArgumentException ("uri must be absolute.", "absoluteUri");
  64 #endif
  65
  66                         if (absoluteUri.Scheme == "file") {
  67                                 if (absoluteUri.AbsolutePath == String.Empty)
  68                                         throw new ArgumentException ("uri must be absolute.", "absoluteUri");
  69                                 return new FileStream (UnescapeRelativeUriBody (absoluteUri.LocalPath), FileMode.Open, FileAccess.Read, FileShare.Read);
  70                         }
  71
  72                         // (MS documentation says) parameter role isn't used yet.
  73                         WebRequest req = WebRequest.Create (absoluteUri);
  74                         if (credential != null)
  75                                 req.Credentials = credential;
  76                         return req.GetResponse().GetResponseStream();
  77                 }
  78
  79 #if NET_2_0
  80                 public override Uri ResolveUri (Uri baseUri, string relativeUri)
  81                 {
  82                         return base.ResolveUri (baseUri, relativeUri);
  83                 }
  84 #endif
  85
  86                 // see also XmlResolver.EscapeRelativeUriBody().
  87                 private string UnescapeRelativeUriBody (string src)
  88                 {
  89                         return src.Replace ("%3C", "<")
  90                                 .Replace ("%3E", ">")
  91                                 .Replace ("%23", "#")
  92                                 .Replace ("%22", "\"")
  93                                 .Replace ("%20", " ")
  94                                 .Replace ("%25", "%");
  95                 }
  96         }
  97 }