mcs/class/System.Web/System.Web.UI/XPathBinder.cs

   1 //
   2 // System.Web.UI.XPathBinder
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@users.sourceforge.net)
   6 //
   7 // (C) 2003 Ben Maurer
   8 //
   9
  10 #if NET_1_2
  11 using System.Collections;
  12 using System.Collections.Specialized;
  13 using System.Text;
  14 using System.Xml.XPath;
  15 using System.Xml;
  16
  17 namespace System.Web.UI {
  18         public sealed class XPathBinder {
  19                 private XPathBinder ()
  20                 {
  21                 }
  22
  23                 public static object Eval (object container, string xpath)
  24                 {
  25                         if (xpath == null || xpath.Length == 0)
  26                                 throw new ArgumentNullException ("xpath");
  27
  28                         IXPathNavigable factory = container as IXPathNavigable;
  29
  30                         if (factory == null)
  31                                 throw new ArgumentException ("container");
  32
  33                         object result = factory.CreateNavigator ().Evaluate (xpath);
  34
  35                         XPathNodeIterator itr = result as XPathNodeIterator;
  36                         if (itr != null) {
  37                                 if (itr.MoveNext())
  38                                         return itr.Current.Value;
  39                                 else
  40                                         return null;
  41                         }
  42                         return result;
  43                 }
  44
  45                 public static string Eval (object container, string xpath, string format)
  46                 {
  47                         object result = Eval (container, xpath);
  48
  49                         if (result == null)
  50                                 return String.Empty;
  51                         if (format == null || format.Length == 0)
  52                                 return result.ToString ();
  53
  54                         return String.Format (format, result);
  55                 }
  56
  57                 public static IEnumerable Select (object container, string xpath)
  58                 {
  59                         if (xpath == null || xpath.Length == 0)
  60                                 throw new ArgumentNullException ("xpath");
  61
  62                         IXPathNavigable factory = container as IXPathNavigable;
  63
  64                         if (factory == null)
  65                                 throw new ArgumentException ("container");
  66
  67                         XPathNodeIterator itr = factory.CreateNavigator ().Select (xpath);
  68                         ArrayList ret = new ArrayList ();
  69
  70                         while (itr.MoveNext ()) {
  71                                 IHasXmlNode nodeAccessor = itr.Current as IHasXmlNode;
  72                                 if (nodeAccessor == null)
  73                                         throw new InvalidOperationException ();
  74                                 ret.Add (nodeAccessor.GetNode ());
  75                         }
  76                         return ret;
  77                 }
  78
  79         }
  80 }
  81 #endif
  82