c# - How do I update the value of a complex object within another object? -

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Considering the following two classes, which are representing tables in the database, I have a stack of MyClass I want to set the statetipe db has two predefined values. 

  public class MyClass {[Key] public int id {get; Set; } Public string name {get; Set; } [Datatype (datatype multiline text)] public string description {get; Set; } Public virtual status type type {get; Set; }} Public Class Statutes {Public Ent ID {get; Set; } Public virtual iconging & lt; MyClass & gt; Receive {myclasses; Set; } Datatype (datatype multiline text)] public string description {get; Set; }}   
 is a third table (MyClass_StatusType) that does not represent by an entity that acts as more than one intermediary.  
 My code:  
  MyClass MC = New MyClass (); Mc.Description = "description"; McStatusType.Id = 3; Db.MyClasses.Add (MC); Var id = db.SaveChanges ();   
 There is a record in my status with an ID of 3. When I run this code, I get an empty reference exception on StatusType.  
 What is the correct way to set this price in MyClass?   
 
 
 You receive exceptions due to access to StatusType in this line  
 < Code> mc.StatusType.Id = 3;   
 MC is a new object and it does not have any statistic type defined.  
  1)  The best way to correct this is to use the FK Field Statistic ID  
  mc.StatusTypeId = 3;   
  2)  But if you can not use this field then the second solution is the following:  
 You should instead of setting the ID Set it to an existing type (of a non existing current type). Creates an additional goaltrip in DB to get static type object.  
  var status type = MyMethodToGetExistingStatusType (3); McStatusType = statusType;   
 I do not know how you can get your type of examples but in the method  MyMethodToGetExistingStatusType ()  you can handle it.  
 I hope this will help you?

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