Experiments/Attic/Winforms/AssemblyResolverDialog/Castle.Components.Winforms.AssemblyResolver/AssemblyResolverComponent.cs

   1 // Copyright 2004-2008 Castle Project - http://www.castleproject.org/
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 namespace Castle.Components.Winforms.AssemblyResolver
  16 {
  17         using System;
  18         using System.Reflection;
  19         using System.Collections.Specialized;
  20         using System.Windows.Forms;
  21
  22         using Castle.Core;
  23
  24         /// <summary>
  25         /// This component installs an Assembly Resolver delegate that
  26         /// asks the user for the location of the missing assembly. Once provided
  27         /// it caches the location.
  28         /// </summary>
  29         [CastleComponent("assembly.resolver")]
  30         public class AssemblyResolverComponent : IStartable
  31         {
  32                 private String lastAssemblyPath;
  33                 private HybridDictionary name2Assembly = new HybridDictionary();
  34
  35                 public AssemblyResolverComponent()
  36                 {
  37                 }
  38
  39                 #region IStartable Members
  40
  41                 public void Start()
  42                 {
  43                         AppDomain.CurrentDomain.AssemblyResolve +=
  44                                 new ResolveEventHandler(CurrentDomain_AssemblyResolve);
  45                 }
  46
  47                 public void Stop()
  48                 {
  49                         AppDomain.CurrentDomain.AssemblyResolve -=
  50                                 new ResolveEventHandler(CurrentDomain_AssemblyResolve);
  51                 }
  52
  53                 #endregion
  54
  55                 private Assembly CurrentDomain_AssemblyResolve(object sender, ResolveEventArgs args)
  56                 {
  57                         Assembly assembly = null;
  58
  59                         String name = AssemblyUtils.Normalize(args.Name);
  60
  61                         // Cache
  62                         if (name2Assembly.Contains(name))
  63                         {
  64                                 return name2Assembly[name] as Assembly;
  65                         }
  66
  67                         // Try to load from the last path
  68                         if (lastAssemblyPath != null)
  69                         {
  70                                 assembly = AssemblyUtils.TryToLoadAssembly(lastAssemblyPath, name);
  71
  72                                 if (assembly != null)
  73                                 {
  74                                         UpdateCache(name, assembly);
  75                                         return assembly;
  76                                 }
  77                         }
  78
  79                         // At last, we ask the user for the location
  80                         assembly = ShowForm(args, name);
  81
  82                         if (assembly != null)
  83                         {
  84                                 UpdateCache(name, assembly);
  85                                 return assembly;
  86                         }
  87
  88                         // All went wrong.
  89                         // Could not find it.
  90
  91                         return null;
  92                 }
  93
  94                 private Assembly ShowForm(ResolveEventArgs args, string name)
  95                 {
  96                         LocateAssemblyForm form = new LocateAssemblyForm(args.Name);
  97                         DialogResult result = DialogResult.Abort;
  98
  99                         if (Form.ActiveForm != null)
 100                         {
 101                                 result = form.ShowDialog(Form.ActiveForm);
 102                         }
 103                         else
 104                         {
 105                                 result = form.ShowDialog();
 106                         }
 107
 108                         if (result == DialogResult.OK)
 109                         {
 110                                 lastAssemblyPath = form.AssemblyLocation;
 111
 112                                 return form.AssemblyLoaded;
 113                         }
 114
 115                         return null;
 116                 }
 117
 118                 private void UpdateCache(string name, Assembly loaded)
 119                 {
 120                         name2Assembly[name] = loaded;
 121                 }
 122         }
 123 }