c# - How to use a specific value from database in mvc validations -

i have value e.g. "not interested" in database. need put validation on 1 of entity using specific value "note interested"

public class {callnote} {     public datetime callback {get; set;} } 

i trying in way getting error of object referance.

public class futuredateattribute : validationattribute {     public override bool isvalid(object value)     {         string feed = "not interested"         mydbcontext db = new mydbcontext();         var temp = db.savedfeedback.feedback.feedbackdropdown.except(feed).any();         if(temp.tostring() == null)         {             return value != null && (datetime)value > datetime.now         }         else              return value == null     } } 

what right linq query , condition in case? newbie

after line var temp = db.savedfeedback.feedback.feedbackdropdown.except(feed).any(); if want check value of temp, should check bool like

if(temp) {  // true //do logic } else {  //this false //do logic }