Question

I’ve a procedure where I need to save an entity object. The problem is that I don’t know if this entity is attached to my datacontext or not. To solve this I use the following code:

try {     db.ClientUsers.Attach(clientUser);     db.Refresh(RefreshMode.KeepCurrentValues, clientUser); } catch { }  db.SubmitChanges();  

I’m looking for a better method to detect if an entity belongs to a context and also to test if an entity is attached to a specific context.

Answer 1

I wonder… what does GetOriginalEntityState return for a non-attached object? Even if it throws an exception, it’ll probably be faster than a refresh…

(update) – a test shows it returns null:

        Customer cust = new Customer();         Customer orig = ctx.Customers.GetOriginalEntityState(cust);         Assert.IsNull(orig);          cust = new Customer();         ctx.Customers.Attach(cust);         orig = ctx.Customers.GetOriginalEntityState(cust);         Assert.IsNotNull(orig);         Assert.AreNotSame(cust,orig); 

So perhaps use GetOriginalEntityState and check for null returned value…