C＃实体框架，如何从通过Junction表创建的对象中获取主键

Question

Create new APN Object and add IPSec object via the IPSecs Junction table. I then need to add the new IPSecID (primary Key) to the BuildType table.

APN newApn = new APN()

 newApn.IPSecs.Add(new IPSec
    {
                    EndPoint = vtcPriEndPoint.Text,
    }


newApn.BuildTypes.Add(new BuildType
                    {
                    TypeOfBuild = "IPsec",
                    TransportID = newApn.IPSecID   <---no option for this syntax
                     }

Answer 1

As you have defined a many to many relation between APN and IPSec you will have to for each through the newApn's IPSecs and create BuildTypes for each of them.

That said, the Id of the new IPSecs will not be known until after you have called SaveChanges on the context. Alternatively you can assign each IPSec of the newAPN to the BuildType 's supposed Transport Navigation property.