MonoRail/Castle.MonoRail.Framework/Attributes/HelperAttribute.cs

   1 // Copyright 2004-2007 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.MonoRail.Framework
  16 {
  17         using System;
  18         using Castle.MonoRail.Framework.Descriptors;
  19
  20         /// <summary>
  21         /// Associates a helper class with the controller.
  22         /// </summary>
  23         [AttributeUsage(AttributeTargets.Class, AllowMultiple=true), Serializable]
  24         public class HelperAttribute : Attribute, IHelperDescriptorBuilder
  25         {
  26                 private readonly Type helperType;
  27                 private readonly String name;
  28
  29                 /// <summary>
  30                 /// Constructs a <see cref="HelperAttribute"/>
  31                 /// with the supplied <c>helperType</c>.
  32                 /// </summary>
  33                 /// <param name="helperType">The helper type</param>
  34                 public HelperAttribute(Type helperType) : this(helperType, null)
  35                 {
  36                 }
  37
  38                 /// <summary>
  39                 /// Constructs a <see cref="HelperAttribute"/>
  40                 /// with the supplied <c>helperType</c> and a name to be bound to it.
  41                 /// </summary>
  42                 /// <param name="helperType">The helper type</param>
  43                 /// <param name="name">Name bound to the helper. The name will be
  44                 /// used on the view to gain access to it</param>
  45                 public HelperAttribute(Type helperType, String name)
  46                 {
  47                         this.helperType = helperType;
  48                         this.name = (name == null || name.Trim() == String.Empty) ? helperType.Name : name;
  49                 }
  50
  51                 /// <summary>
  52                 /// Gets Name bound to the helper. The name will be
  53                 /// used on the view to gain access to it
  54                 /// </summary>
  55                 public String Name
  56                 {
  57                         get { return name; }
  58                 }
  59
  60                 /// <summary>
  61                 /// Gets the helper type
  62                 /// </summary>
  63                 public Type HelperType
  64                 {
  65                         get { return helperType; }
  66                 }
  67
  68                 /// <summary>
  69                 /// <see cref="IHelperDescriptorBuilder"/> implementation.
  70                 /// Gets the <seealso cref="HelperDescriptor"/>
  71                 /// that describes the helper.
  72                 /// </summary>
  73                 /// <returns>The descriptor instance</returns>
  74                 public HelperDescriptor[] BuildHelperDescriptors()
  75                 {
  76                         return new HelperDescriptor[] { new HelperDescriptor(helperType, name) };
  77                 }
  78         }
  79 }