Components/Validator/Castle.Components.Validator/Attributes/ValidateNotSameValueAttribute.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.Validator
  16 {
  17         using System;
  18         using System.Reflection;
  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                         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                 /// <summary>
  46                 /// Initializes a new instance of the <see cref="ValidateSameAsAttribute"/> class.
  47                 /// </summary>
  48                 public ValidateNotSameValueAttribute(Type valueType, object mustNotBeThisValue, string errorMessage)
  49                         : base(errorMessage)
  50                 {
  51                         if (mustNotBeThisValue == null)
  52                         {
  53                                 throw new ArgumentException(
  54                                         "You cannot use ValidateNotSameValue validator for null values, use ValidateNotEmpty for this");
  55                         }
  56                         if (typeof(IConvertible).IsAssignableFrom(valueType))
  57                                 value = Convert.ChangeType(mustNotBeThisValue, valueType);
  58                         else
  59                         {
  60                                 MethodBase createInstance = valueType.GetMethod("Parse", BindingFlags.Public | BindingFlags.Static);
  61                                 if (createInstance != null)
  62                                 {
  63                                         value = createInstance.Invoke(null, new object[] {mustNotBeThisValue});
  64                                 }
  65                                 ConstructorInfo ctor = valueType.GetConstructor(new Type[] {mustNotBeThisValue.GetType()});
  66                                 if (ctor == null)
  67                                 {
  68                                         throw new ArgumentException(
  69                                                 "valueType must be a type that implements IConvertible, or have a Parse method, or have a constructor that accept a " +
  70                                                 mustNotBeThisValue.GetType()
  71                                                 );
  72                                 }
  73                                 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 }