MVC Custom Data Annotations

Custom Annotation

/CustomValidation/ValidateAgeAttribute.cs

This can be used to apply a custom range validation to the given date time value.

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Web.Mvc;

namespace PROJECTNAMESPACE.CustomValidation
{
 [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
 public class ValidateAgeAttribute : ValidationAttribute, IClientValidatable
 {
 private const string DefaultErrorMessage = "Your age is invalid, your {0} should fall between {1} and {2}";

public DateTime MinimumDateProperty { get; private set; }
 public DateTime MaximumDateProperty { get; private set; }

public ValidateAgeAttribute(
 int minimumAgeProperty,
 int maximumAgeProperty)
 : base(DefaultErrorMessage)
 {
 MaximumDateProperty = DateTime.Now.AddYears(minimumAgeProperty * -1);
 MinimumDateProperty = DateTime.Now.AddYears(maximumAgeProperty * -1);
 }

protected override ValidationResult IsValid(object value, ValidationContext validationContext)
 {
 if (value != null)
 {
 DateTime parsedValue = (DateTime)value;

if (parsedValue <= MinimumDateProperty || parsedValue >= MaximumDateProperty)
 {
 return new ValidationResult(FormatErrorMessage(validationContext.DisplayName));
 }
 }
 return ValidationResult.Success;

}
 public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
 {
 var rule = new ModelClientValidationRule()
 {
 ValidationType = "validateage",
 ErrorMessage = FormatErrorMessage(metadata.GetDisplayName()),
 };

rule.ValidationParameters.Add("minumumdate", MinimumDateProperty.ToShortDateString());
 rule.ValidationParameters.Add("maximumdate", MaximumDateProperty.ToShortDateString());

yield return rule;
 }

public override string FormatErrorMessage(string name)
 {
 return string.Format(ErrorMessageString, name, MinimumDateProperty.ToShortDateString(), MaximumDateProperty.ToShortDateString());
 }
 }
}

Applied to Model

[Required]
[Display(Name = "Effective From")]
[DisplayFormat(DataFormatString = "{0:dd/MM/yyyy}", ApplyFormatInEditMode = true)]
[ValidateAge(15, 65)]
public DateTime DateOfBirth { get; set; }

Reference

Unobtrusive Client and Server Side Age Validation in MVC using Custom Data Annotations (http://www.macaalay.com)