Entity Framework : update 2 entities with related entity of same key -


"Student" has the navigation property "school" in it. 

  Public class students {public long id; The name of the public string; Public school meschool; } Public class school {public long id; The name of the public string; }   
 To update the database, the client program passes in two student institutions of the same school. Students. Myschool has two students in different subjects school with the same key.Id is .  
 How can I update two students in  a transaction  ?  
 I thought that two students should be paired with DBKNext and then be changed to modify their state. But the second was unsuccessful with the encryption error: Attaching a unit of type 'school' was unsuccessful because another unit of the same type already had primary key value.   
 
 
  MySchoolId  add property to  student  and  MySchoolId  set the reference to  MySchool  faucets before adding students to the context of each student's property  myschool  context, and then reference.  
  Public long term MySchoolId {get; Set; }   
 You may have to check whether the school is already present in the context or not. If not, add it to the context, save the reference, and use the latest update  id  of a school unit to set the value of  MySchoolId  property .  
 Alternatively, you can ask for a match school reference and set the property of each student in the unit that came from context or you just made it.

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