Components/General/Validator/Castle.Components.Validator/Attributes/ValidateNotSameValueAttribute.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 using System;
  16 using System.Reflection;
  17
  18 namespace Castle.Components.Validator
  19 {
  20     /// <summary>
  21     /// Validates that the content has not been set to the specified value
  22     /// </summary>
  23     public class ValidateNotSameValueAttribute : AbstractValidationAttribute
  24     {
  25         private readonly object value;
  26
  27         /// <summary>
  28         /// Initializes a new instance of the <see cref="ValidateSameAsAttribute"/> class.
  29         /// </summary>
  30         public ValidateNotSameValueAttribute(object mustNotBeThisValue)
  31         {
  32             this.value = mustNotBeThisValue;
  33         }
  34
  35         /// <summary>
  36         /// Initializes a new instance of the <see cref="ValidateNotSameValueAttribute"/> class.
  37         /// </summary>
  38         /// <param name="valueType">Type of the value.</param>
  39         /// <param name="mustNotBeThisValue">The must not be this value.</param>
  40          public ValidateNotSameValueAttribute(Type valueType, object mustNotBeThisValue)
  41                 :this(valueType,mustNotBeThisValue, null)
  42          {
  43
  44          }
  45
  46         /// <summary>
  47         /// Initializes a new instance of the <see cref="ValidateSameAsAttribute"/> class.
  48         /// </summary>
  49         public ValidateNotSameValueAttribute(Type valueType, object mustNotBeThisValue, string errorMessage)
  50             : base(errorMessage)
  51         {
  52             if (mustNotBeThisValue==null)
  53             {
  54                 throw new ArgumentException(
  55                     "You cannot use ValidateNotSameValue validator for null values, use ValidateNotEmpty for this");
  56             }
  57             if (typeof(IConvertible).IsAssignableFrom(valueType))
  58                 this.value = Convert.ChangeType(mustNotBeThisValue, valueType);
  59             else
  60             {
  61                 MethodBase createInstance = valueType.GetMethod("Parse",BindingFlags.Public|BindingFlags.Static);
  62                 if(createInstance!=null)
  63                 {
  64                     this.value = createInstance.Invoke(null, new object[] { mustNotBeThisValue });
  65                 }
  66                 ConstructorInfo ctor = valueType.GetConstructor(new Type[] { mustNotBeThisValue.GetType() });
  67                 if(ctor==null)
  68                 {
  69                     throw new ArgumentException(
  70                         "valueType must be a type that implements IConvertible, or have a Parse method, or have a constructor that accept a " + mustNotBeThisValue.GetType()
  71                         );
  72                 }
  73                 this.value = Activator.CreateInstance(valueType, mustNotBeThisValue);
  74             }
  75         }
  76
  77         /// <summary>
  78         /// Constructs and configures an <see cref="IValidator"/>
  79         /// instance based on the properties set on the attribute instance.
  80         /// </summary>
  81         /// <returns></returns>
  82         public override IValidator Build()
  83         {
  84             IValidator validator = new NotSameValueValidator(value);
  85             ConfigureValidatorMessage(validator);
  86             return validator;
  87         }
  88     }
  89 }