Entity Framework 5 Updating a Record

Question

I have been exploring different methods of editing/updating a record within Entity Framework 5 in an ASP.NET MVC3 environment, but so far none of them tick all of the boxes I need. I'll explain why.

I have found three methods to which I'll mention the pros and cons:

Method 1 - Load original record, update each property

var original = db.Users.Find(updatedUser.UserId);  if (original != null) {     original.BusinessEntityId = updatedUser.BusinessEntityId;     original.Email = updatedUser.Email;     original.EmployeeId = updatedUser.EmployeeId;     original.Forename = updatedUser.Forename;     original.Surname = updatedUser.Surname;     original.Telephone = updatedUser.Telephone;     original.Title = updatedUser.Title;     original.Fax = updatedUser.Fax;     original.ASPNetUserId = updatedUser.ASPNetUserId;     db.SaveChanges(); }     

Pros

• Can specify which properties change
• Views don't need to contain every property

Cons

• 2 x queries on database to load original then update it

Method 2 - Load original record, set changed values

var original = db.Users.Find(updatedUser.UserId);  if (original != null) {     db.Entry(original).CurrentValues.SetValues(updatedUser);     db.SaveChanges(); } 

Pros

• Only modified properties are sent to database

Cons

• Views need to contain every property
• 2 x queries on database to load original then update it

Method 3 - Attach updated record and set state to EntityState.Modified

db.Users.Attach(updatedUser); db.Entry(updatedUser).State = EntityState.Modified; db.SaveChanges(); 

Pros

• 1 x query on database to update

Cons

• Can't specify which properties change
• Views must contain every property

Question

My question to you guys; is there a clean way that I can achieve this set of goals?

• Can specify which properties change
• Views don't need to contain every property (such as password!)
• 1 x query on database to update

I understand this is quite a minor thing to point out but I may be missing a simple solution to this. If not method one will prevail ;-)

Answer 1

You are looking for:

db.Users.Attach(updatedUser); var entry = db.Entry(updatedUser); entry.Property(e => e.Email).IsModified = true; // other changed properties db.SaveChanges(); 

Answer 2

I really like the accepted answer. I believe there is yet another way to approach this as well. Let's say you have a very short list of properties that you wouldn't want to ever include in a View, so when updating the entity, those would be omitted. Let's say that those two fields are Password and SSN.

db.Users.Attach(updatedUser);  var entry = db.Entry(updatedUser); entry.State = EntityState.Modified;  entry.Property(e => e.Password).IsModified = false; entry.Property(e => e.SSN).IsModified = false;     db.SaveChanges();    

This example allows you to essentially leave your business logic alone after adding a new field to your Users table and to your View.