无法定义关系，因为它们已附加到不同的ObjectContext对象

Question

I don't know what i'm missing, as the same page_load is executed no matter how the page is called, but when i quit the page without saving anything, and then go back into the page, it seems like my context object is not able to retreive the usaved values like it does when i do save the changes before quitting the page, leading me to this exeption when i try to save from there :

Unable to set the relationship between the two objects , as they are attached to different ObjectContext objects.

here is what i have in the page load :

public partial class FraisDeplacement : System.Web.UI.UserControl
{
    BLL.SessionContext context;
    DAL.DBObjects.VersionDemande versionDemande;


    protected void Page_Load(object sender, EventArgs e)
    {
        this.context = (BLL.SessionContext)Session["sessionContext"];

        this.Page.LoadComplete += new EventHandler(Page_LoadComplete);

        versionDemande = (DAL.DBObjects.VersionDemande)Session["versionDemande"];

    }

}

Answer 1

I had this problem too, you probably need one of those two functions :

context.DBAccess.Attach(versionDemande);

or this one

versionDemande = this.context.DBAccess.ApplyCurrentValues<DAL.DBObjects.VersionDemande>("VersionDemande", versionDemande);

depending on how your objects are created/retreived on the page, i recommend you to put these into try catch at first, it will help you to see what is going on if they fail.