ASP.NET MVC: Custom Validation by DataAnnotation with client side

You could write a custom validation attribute:

public class CombinedMinLengthAttribute: ValidationAttribute
{
    public CombinedMinLengthAttribute(int minLength, params string[] propertyNames)
    {
        this.PropertyNames = propertyNames;
        this.MinLength = minLength;
    }

    public string[] PropertyNames { get; private set; }
    public int MinLength { get; private set; }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        var properties = this.PropertyNames.Select(validationContext.ObjectType.GetProperty);
        var values = properties.Select(p => p.GetValue(validationContext.ObjectInstance, null)).OfType<string>();
        var totalLength = values.Sum(x => x.Length) + Convert.ToString(value).Length;
        if (totalLength < this.MinLength)
        {
            return new ValidationResult(this.FormatErrorMessage(validationContext.DisplayName));
        }
        return null;
    }
}

and then you might have a view model and decorate one of its properties with it:

public class MyViewModel
{
    [CombinedMinLength(20, "Bar", "Baz", ErrorMessage = "The combined minimum length of the Foo, Bar and Baz properties should be longer than 20")]
    public string Foo { get; set; }
    public string Bar { get; set; }
    public string Baz { get; set; }
}

client side

---------------

<script src="@Url.Content("~/Scripts/jquery-1.8.2.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.js")" type="text/javascript"></script>



<script type="text/javascript">
    // we add a custom jquery validation method
    jQuery.validator.addMethod('greaterThan', function (value, element, params) {
        if (!/Invalid|NaN/.test(new Date(value))) {
            return new Date(value) > new Date($(params).val());
        }
        return isNaN(value) && isNaN($(params).val()) || (parseFloat(value) > parseFloat($(params).val()));
    }, '');

    // and an unobtrusive adapter
    jQuery.validator.unobtrusive.adapters.add('futuredate', {}, function (options) {
        options.rules['greaterThan'] = true;
        options.messages['greaterThan'] = options.message;
    });

   
    $.validator.addMethod("exclude", function (value, element, exclude) {
        if (value) {
            for (var i = 0; i < exclude.length; i++) {
                if (jQuery.inArray(exclude[i], value) != -1) {
                    return false;
                }
            }
        }
        return true;
    });

    $.validator.unobtrusive.adapters.addSingleVal("exclude", "chars");

</script>
  public class custome
    {
        [CombinedMinLengthAttribute("name ", ErrorMessage="fdgd")]
        public string name { get; set; }
        public string address { get; set; }
        [FutureDate(ErrorMessage = "Should be in the future")]
        public DateTime Date { get; set; }
    }

public class FutureDateAttribute : ValidationAttribute, IClientValidatable
    {
        public override bool IsValid(object value)
        {
            if (value == null || (DateTime)value < DateTime.Now)
                return false;

            return true;
        }

        public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
        {
            yield return new ModelClientValidationRule
            {
                ErrorMessage = this.ErrorMessage,
                ValidationType = "futuredate"
            };
        }
    }