Question

I am trying to put some distributed caching into play, I’m using this indeXus.Net Shared Cache .

It Requires that the object being cached is serializable, which it is here is the class object.

[Serializable] public class Members  {     public Members()     {}      public Members(string aspnetusername, string aspnetpassword,         string emailaddr,string location)         : this(0,0,aspnetusername, aspnetpassword,emailaddr,DateTime.Now, location,         0,0,DateTime.Now,DateTime.Now,DateTime.Now,false)     { }      public Members(Int64? row,int memberid, string aspnetusername, string aspnetpassword,         string emailaddr,DateTime datecreated, string location, int daimokugoal, int previewimageid,         DateTime lastdaimoku, DateTime lastnotifed, DateTime lastactivitydate, bool isactivated)     {         this.Row = row;         this.MemberID = memberid;         this.Aspnetusername = aspnetusername;         this.Aspnetpassword = aspnetpassword;         this.EmailAddr = emailaddr;         this.DateCreated = datecreated;         this.Location = location;         this.DaimokuGoal = daimokugoal;         this.PreviewImageID = previewimageid;         this.LastDaimoku = lastdaimoku;         this.LastNotefied = lastnotifed;         this.LastActivityDate = lastactivitydate;         this.IsActivated = this.IsActivated;         this.Details = new LazyList<MemberDetails>();         this.Blogs = new LazyList<MemberBlogs>();         this.Daimoku = new LazyList<MemberDaimoku>();         this.Determinations = new LazyList<MemberDeterminations>();         this.Encouragements = new LazyList<MemberEncouragements>();         this.Entries = new LazyList<MemberEntries>();         this.Friends = new LazyList<MemberFriends>();         this.Stats = new LazyList<MemberStats>();       }       public Int64? Row { get; set; }         public int MemberID { get; set; }    public string Aspnetusername { get; set; }    public string Aspnetpassword { get; set; }    public string EmailAddr { get; set; }    public DateTime DateCreated { get; set; }    public string Location { get; set; }    public int DaimokuGoal { get; set; }    public int PreviewImageID { get; set; }    public DateTime LastDaimoku { get; set; }    public DateTime LastNotefied { get; set; }    public DateTime LastActivityDate { get; set; }    public bool IsActivated { get; set; }    public LazyList<MemberDetails> Details { get; set; }    public LazyList<MemberBlogs> Blogs { get; set; }    public LazyList<MemberDaimoku> Daimoku { get; set; }    public LazyList<MemberDeterminations> Determinations { get; set; }    public LazyList<MemberEncouragements> Encouragements { get; set; }    public LazyList<MemberEntries> Entries { get; set; }    public LazyList<MemberFriends> Friends { get; set; }    public LazyList<MemberStats> Stats { get; set; } } 

The LINQtoSql is this that populates this class.

  public IQueryable<Members> GetMemberInfo()       {           using (var t = new TransactionScope(TransactionScopeOption.Required,                     new TransactionOptions { IsolationLevel = System.Transactions.IsolationLevel.ReadUncommitted }))           {               var results = from m in _datacontext.ViewMembers                             let details = GetMemberDetails(m.MemberID)                             let determinations = GetMemberDeterminations(m.MemberID)                             let daimoku = GetMemberDaimoku(m.MemberID)                             let entries = GetMemberEntries(m.MemberID)                             let blogs = GetMemberBlogs(m.MemberID)                             let encouragements = GetMemberEncouragements(m.MemberID)                             let friends = GetMemberFriends(m.MemberID)                             let points = GetMemberStats(m.MemberID)                             select new Members                             {                                 Row = m.Row,                                 MemberID = m.MemberID,                                 Aspnetusername = m.Aspnetusername,                                 Aspnetpassword = m.Aspnetpassword,                                 EmailAddr = m.EmailAddr,                                 DateCreated = m.DateCreated,                                 Location = m.Location,                                 DaimokuGoal = m.DaimokuGoal,                                 PreviewImageID = m.PreviewImageID,                                 LastDaimoku = m.LastDaimoku.Value,                                 LastNotefied = m.LastNotefied.Value,                                 LastActivityDate = m.LastActivityDate.Value,                                 IsActivated = m.IsActivated,                                 Details = new LazyList<MemberDetails>(details),                                 Determinations = new LazyList<MemberDeterminations>(determinations),                                 Daimoku = new LazyList<MemberDaimoku>(daimoku),                                 Entries = new LazyList<MemberEntries>(entries),                                 Blogs = new LazyList<MemberBlogs>(blogs),                                 Encouragements = new LazyList<MemberEncouragements>(encouragements),                                 Friends = new LazyList<MemberFriends>(friends),                                 Stats = new LazyList<MemberStats>(points)                             };               return results;           }       } 

But for some reason I am getting this error

System.Runtime.Serialization.SerializationException: Type ‘System.Data.Linq.DataQuery`1[[DaimokuBeta.MVC.Data.MemberDetails, DaimokuBeta.MVC.Data, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]’ in Assembly ‘System.Data.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089’ is not marked as serializable.

MemberDetails is serializable too..so not sure why it thinks it can’t be serialized Any ideas?

Answer 1

I believe that it’s your LazyList implementation that cannot be serialized because the exception is telling us that the generic type DataQuery (from assembly System.Data.Linq) is not serializable. Is this type connected to your LazyList in any way?

If you are trying to cache the Members DTO (data transfer object) it’s probably not a good idea to be applying lazy loading because it may only be executed in a very unpredictable moment.

Cache should usually be applied to data that has already been loaded/computed. Otherwise there may not be much point in using cache.