Cloning data on Entity Framework [duplicate]

Solution 1:

To clone an Entity in Entity Framework you could simply Detach the entity from the DataContext and then re-add it to the EntityCollection.

context.Detach(entity);
entityCollection.Add(entity);

Update for EF6+ (from comments)

context.Entry(entity).State = EntityState.Detached;
entity.id = 0;
entity.property = value;
context.Entry(entity).State = EntityState.Added;
context.SaveChanges();

Solution 2:

public static EntityObject Clone(this EntityObject Entity)
{
    var Type = Entity.GetType();
    var Clone = Activator.CreateInstance(Type);

    foreach (var Property in Type.GetProperties(BindingFlags.GetProperty | BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly | BindingFlags.SetProperty))
    {
        if (Property.PropertyType.IsGenericType && Property.PropertyType.GetGenericTypeDefinition() == typeof(EntityReference<>)) continue;
        if (Property.PropertyType.IsGenericType && Property.PropertyType.GetGenericTypeDefinition() == typeof(EntityCollection<>)) continue;
        if (Property.PropertyType.IsSubclassOf(typeof(EntityObject)))  continue;

        if (Property.CanWrite)
        {
            Property.SetValue(Clone, Property.GetValue(Entity, null), null);
        }
    }

    return (EntityObject)Clone;
}

This is a simple method I wrote. It should work for most people.

Solution 3:

To add a new row whose content is based on an existing row, follow these steps:

1. Get an entity based on the starting row.
2. Set the entry state for the entity to Added.
3. Modify the entity.
4. Save changes.

Here's an example:

var rabbit = db.Rabbits.First(r => r.Name == "Hopper");
db.Entry(rabbit).State = EntityState.Added;
rabbit.IsFlop = false;
db.SaveChanges();