Custom ValidationAttribute test against whole model

Question

I know this is probably not possible but let\'s say I have a model with two properties.

I write a ValidationAttribute for one of the properties. Can that VA look at

Answer 1

Use ValidationContext to get your model:

 public class MyRequiredValidator: RequiredAttribute
    {
        public override bool RequiresValidationContext
        {
            get {return true;} //it needs another propertie in model            
        }

        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            QuickQuote model = (QuickQuote)validationContext.ObjectInstance;

            if (model.state == "single")
                return null;
            else
                return base.IsValid(value, validationContext);//familyType is require for married
        }      
    }