--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Source/Validation/Validator.cs	Thu Mar 27 21:46:09 2014 +0400
@@ -0,0 +1,212 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+
+using BLToolkit.Reflection;
+
+namespace BLToolkit.Validation
+{
+	public class Validator
+	{
+		#region Validate
+
+		public static void Validate(ValidationContext context)
+		{
+			foreach (MemberAccessor ma in context.TypeAccessor)
+			{
+				var attrs = ma.GetAttributes<ValidatorBaseAttribute>();
+
+				if (attrs == null)
+					continue;
+
+				context.MemberAccessor = ma;
+				context.Value          = ma.GetValue(context.Object);
+
+				for (var i = 0; i < attrs.Length; i++)
+				{
+					var attr = attrs[i];
+					if (attr.IsValid(context) == false)
+						throw new ValidationException(attr.GetErrorMessage(context));
+				}
+			}
+		}
+
+		public static void Validate(object obj, ValidationContext.IsNullHandler isNull)
+		{
+			Validate(InitContext(null, obj, null, isNull));
+		}
+
+		public static void Validate(object obj)
+		{
+			Validate(obj, null);
+		}
+
+		#endregion
+
+		#region Protected Members
+
+		private static bool IsNullInternal(ValidationContext context)
+		{
+			if (context.Value == null)
+				return true;
+
+			if (context.NullValue is DBNull)
+				return false;
+
+			return context.NullValue.Equals(context.Value);
+		}
+
+		public static ValidationContext InitContext(
+			ValidationContext  context,
+			object             obj,
+			PropertyDescriptor pd,
+			ValidationContext.IsNullHandler isNull)
+		{
+			if (context == null)
+				context = new ValidationContext();
+
+			context.Object = obj;
+			context.IsNull = isNull ?? new ValidationContext.IsNullHandler(IsNullInternal);
+			context.PropertyDescriptor = pd;
+
+			return context;
+		}
+
+		#endregion
+
+		#region IsValid
+
+		public static bool IsValid(ValidationContext context, string fieldName)
+		{
+			ValidatorBaseAttribute[] attrs = null;
+			object                   value = null;
+
+#if !SILVERLIGHT
+
+			if (context.PropertyDescriptor != null)
+			{
+				value = context.PropertyDescriptor.GetValue(context.Object);
+
+				List<ValidatorBaseAttribute> list = null;
+
+				foreach (var o in context.PropertyDescriptor.Attributes)
+				{
+					if (o is ValidatorBaseAttribute)
+					{
+						if (list == null)
+							list = new List<ValidatorBaseAttribute>();
+
+						list.Add((ValidatorBaseAttribute)o);
+					}
+				}
+
+				if (list != null)
+					attrs = list.ToArray();
+			}
+			else
+
+#endif
+
+			{
+				context.MemberAccessor = context.TypeAccessor[fieldName];
+
+				if (context.MemberAccessor != null)
+				{
+					value = context.MemberAccessor.GetValue(context.Object);
+					attrs = context.MemberAccessor.GetAttributes<ValidatorBaseAttribute>();
+				}
+			}
+
+			if (attrs != null)
+			{
+				context.Value = value;
+
+				for (var i = 0; i < attrs.Length; i++)
+				{
+					if (!attrs[i].IsValid(context))
+						return false;
+				}
+			}
+
+			return true;
+		}
+
+		public static bool IsValid(object obj, string fieldName, ValidationContext.IsNullHandler isNull)
+		{
+			return IsValid(InitContext(null, obj, null, isNull), fieldName);
+		}
+
+#if !SILVERLIGHT
+
+		public static bool IsValid(object obj, PropertyDescriptor pd, ValidationContext.IsNullHandler isNull)
+		{
+			return IsValid(InitContext(null, obj, pd, isNull), pd.Name);
+		}
+
+		public static bool IsValid(object obj, PropertyDescriptor pd)
+		{
+			return IsValid(obj, pd, null);
+		}
+
+#endif
+
+		public static bool IsValid(object obj, string fieldName)
+		{
+			return IsValid(obj, fieldName, null);
+		}
+
+		#endregion
+
+		#region GetErrorMessages
+
+		public static string[] GetErrorMessages(ValidationContext context, string fieldName)
+		{
+			context.MemberAccessor = context.TypeAccessor[fieldName];
+
+			if (context.MemberAccessor != null)
+			{
+				var messages = new List<string>();
+				var attrs    = context.MemberAccessor.GetAttributes<ValidatorBaseAttribute>();
+
+				if (attrs != null)
+				{
+					context.Value = context.MemberAccessor.GetValue(context.Object);
+
+					for (var i = 0; i < attrs.Length; i++)
+						messages.Add(attrs[i].GetErrorMessage(context));
+
+					return messages.ToArray();
+				}
+			}
+
+			return new string[0];
+		}
+
+		public static string[] GetErrorMessages(
+			object obj, string fieldName, ValidationContext.IsNullHandler isNull)
+		{
+			return GetErrorMessages(InitContext(null, obj, null, isNull), fieldName);
+		}
+
+#if !SILVERLIGHT
+
+		public static string[] GetErrorMessages(object obj, PropertyDescriptor pd, ValidationContext.IsNullHandler isNull)
+		{
+			return GetErrorMessages(InitContext(null, obj, pd, isNull), pd.Name);
+		}
+
+		public static string[] GetErrorMessages(object obj, PropertyDescriptor pd)
+		{
+			return GetErrorMessages(obj, pd, null);
+		}
+
+#endif
+
+		public static string[] GetErrorMessages(object obj, string fieldName)
+		{
+			return GetErrorMessages(obj, fieldName, null);
+		}
+
+		#endregion
+	}
+}