Question

Net MVC 3 for development.
Now there is a scenario where i need to create to a custom validator on a collection property.
Now the problem I am facing is that this custom validator works well when the length of the collection is 1 but when there are more than one elements in the collection i face a problem is the custom validation pushes errors but the problem occurs that when checked in ModelState the error is not found plugged. So in this case what should i do ? I am pasting in the code as below.

This is the Model i want to validate:

public class CreateTestModel
{
    [Required]
    public string Name { get; set; }

    public string Description { get; set; }

    public RadioButtonListViewModel<GoalTypes> Goals { get; set; }

    [MinimumRequired("IncludedEntities", "ExcludedEntities", 1, ErrorMessage = "1   Entity is compulsory")]
    public IEnumerable<TestEntityModel> IncludedEntities { get; set; }

    public IEnumerable<TestEntityModel> ExcludedEntities { get; set; }

    public IEnumerable<TestFilterModel> IncludedFilters { get; set; }

    public IEnumerable<TestFilterModel> ExcludedFilters { get; set; }

    public IEnumerable<BucketModel> Buckets { get; set; }

    public bool AutoDecision { get; set; }

    public DateTime StartDate { get; set; }

    public DateTime EndDate { get; set; }

    public int AdminId { get; set; }

    [DefaultValue(true)]
    public bool IsEnabled { get; set; }
  }

Purpose of the Custom Validator:-
I need to validate minimum number of required entities in a collection.
There are some scenarios when for eg in this case : The IncludedEntities and the ExcludedEntities needs to have a minimum count of 1 including both the properties ,this is my business rule.
So for this the Below custom Validator is written.

This is the Custom Validator i have written :

  [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
public class MinimumRequired : ValidationAttribute,IClientValidatable
{
    public int numberOfMandatoryEntities{get; private set;}
    public int totalCountofIncludeEntities { get; private set; }
    public bool isBucket { get; set; }
    public string Property1{get; private set;}
    public string Property2{ get; private set; }
    private const string DefaultErrorMessageFormatString = "Atleast one entity is required";

    public MinimumRequired(string Property1, string Property2, int MandatoryCount)
    {
        this.Property1 = Property1;
        if (!String.IsNullOrEmpty(Property2))
            this.Property2 = Property2;
        numberOfMandatoryEntities = MandatoryCount;
    }


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

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        object property2Value = null;
        object property1Value = null;
        int property1Count=0;
        if(!String.IsNullOrEmpty(Property2))
        property2Value = validationContext.ObjectInstance.GetType().GetProperty(Property2).GetValue(validationContext.ObjectInstance, null);
        property1Value = validationContext.ObjectInstance.GetType().GetProperty(Property1).GetValue(validationContext.ObjectInstance, null);
        if (property1Value != null)
        {
        property1Count = ((IEnumerable<Object>)property1Value).Count();
        }

        if (property2Value != null)
        {
            property1Count = property1Count + ((IEnumerable<Object>)property2Value).Count();
        }
        if (property1Count < numberOfMandatoryEntities)
        {
            return new ValidationResult(ErrorMessage);
        }

        return ValidationResult.Success;
    }
    #region IClientValidatable Members

    public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
    {
        var x = new ModelClientValidationRule();
        x.ValidationType = "entityvalidator";
        x.ErrorMessage = string.Format(ErrorMessageString, metadata.GetDisplayName());
        x.ValidationParameters.Add("mandatoryentity", numberOfMandatoryEntities);
        return new[] 
        {  
            x
        };
    }

    #endregion



}

Please help me out…

Answer 1

I triend the above code it works perfectly for me.