MonoRail/Castle.MonoRail.Framework/Attributes/ViewComponentParamAttribute.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.MonoRail.Framework
  16 {
  17         using System;
  18
  19         /// <summary>
  20         /// Decorates a public property in a <see cref="ViewComponent"/>
  21         /// to have the framework automatically bind the value using
  22         /// the <see cref="ViewComponent.ComponentParams"/> dictionary.
  23         /// </summary>
  24         /// <remarks>
  25         /// By default the property name is going to be used as a key to query the params.
  26         /// <para>
  27         /// You can also use the <see cref="ViewComponentParamAttribute.Required"/>
  28         /// property to define that a parameter is non-optional.
  29         /// </para>
  30         /// </remarks>
  31         /// <example>
  32         /// <para>In the code below, the <c>Text</c> parameter will automatically be bound to the <c>header</c> property.
  33         /// If there is no <c>Text</c> parameter, a <see cref="ViewComponentException"/> will be thrown.</para>
  34         /// Simailrly, the optional <c>CssClass</c> parameter will be bound to the <c>CssClass</c> property.  No error
  35         /// occurs if there is no <c>CssClass</c> parameter.
  36         /// <code><![CDATA[
  37         /// public class HeaderViewComponent : ViewComponent
  38         /// {
  39         ///      [ViewComponentParam("Text", Required= true)]
  40         ///      public string header {get; set;}
  41         ///
  42         ///      [ViewComponentParam]
  43         ///      public string CssClass {get; set;}
  44         ///      // :
  45         ///      // :
  46         /// }
  47         /// ]]></code></example>
  48         /// <seealso cref="ViewComponent"/>
  49         /// <seealso cref="ViewComponentDetailsAttribute"/>
  50         [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true), Serializable]
  51         public class ViewComponentParamAttribute : Attribute
  52         {
  53                 private string paramName;
  54                 private bool required;
  55                 private object defaultValue;
  56
  57                 /// <summary>
  58                 /// Initializes a new instance of the <see cref="ViewComponentParamAttribute"/> class.
  59                 /// </summary>
  60                 public ViewComponentParamAttribute()
  61                 {
  62                 }
  63
  64                 /// <summary>
  65                 /// Initializes a new instance of the <see cref="ViewComponentParamAttribute"/> class
  66                 /// allowing you to override the parameter name to be queried on
  67                 /// the <see cref="ViewComponent.ComponentParams"/> dictionary.
  68                 /// </summary>
  69                 /// <param name="paramName">Overrides the name of the parameter.</param>
  70                 public ViewComponentParamAttribute(string paramName)
  71                 {
  72                         this.paramName = paramName;
  73                 }
  74
  75                 /// <summary>
  76                 /// Gets or sets a value indicating whether a value for this property is required.
  77                 /// </summary>
  78                 /// <value><c>true</c> if required; otherwise, <c>false</c>.</value>
  79                 public bool Required
  80                 {
  81                         get { return required; }
  82                         set { required = value; }
  83                 }
  84
  85                 /// <summary>
  86                 /// Gets the name of the param.
  87                 /// </summary>
  88                 /// <value>The name of the param.</value>
  89                 public string ParamName
  90                 {
  91                         get { return paramName; }
  92                 }
  93
  94                 /// <summary>
  95                 /// Gets or sets the default value for the parameter.
  96                 /// </summary>
  97                 /// <value>The default.</value>
  98                 public object Default
  99                 {
 100                         get { return defaultValue; }
 101                         set { defaultValue = value; }
 102                 }
 103         }
 104 }