json - C# IgnoreDataMember attribute sets database field to null, how do I overcome this? -

i have built web api usual rest methods.

i have field in database tracking when record inserted (called insertlogtime. works fine.

my classes generated automatically ef6 using database first.

i don't want serialised added [ignoredatamember] attribute field using standard partial metadata classes...

[metadatatype(typeof(membersmetadata))] public partial class members { }  public class membersmetadata {     [databasegenerated(databasegeneratedoption.none)]     public int id { get; set; }      [ignoredatamember]     public nullable<datetime> insertlogtime { get; set; } } 

now when use fiddler put data other fields, insertlogtime field set null.

more importantly, don't want show every field put. customer needs use id , single other field. however, need provide full dataset (without insertlogtime) when doing full post.

{ "id":99, "firstname":"jack spratt", "email":"someone@somewhere.com", "eligible":false } 

this works fine when doing post. insert log time ok quick , dirty measure set in controller using datetime.now. know should using default in database i'll later.

ideally customer have insert following when doing put:

{ "id":99, "eligible":true } 

but not sure how this. , mentioned, when use full version use post when doing put, sets insertlogtime field null.

here controller

    [responsetype(typeof(void))]     public ihttpactionresult putmembers(int id, members members)     {         if (!modelstate.isvalid)             return badrequest(modelstate);          if (id != members.id)             return badrequest();          eligible = members.eligible ?? false;          db.entry(members).state = entitystate.modified;          try         {             db.savechanges();         }         catch (dbupdateconcurrencyexception)         {                         //notthing of interest here.         }          return statuscode(httpstatuscode.nocontent);     } 

any overcoming these problems appreciated.