Salin objek Entitas ke objek POCO di mana int Entitas adalah Enum di POCO

Saya mencoba membuat mesin fotokopi menggunakan salinan properti Jon Skeets. Ini berfungsi dengan baik untuk semua properti, tetapi tidak untuk enum. Saya telah mencoba beberapa upaya untuk mengubah metode agar berfungsi untuk enum dan tidak berhasil. Saya bertanya-tanya apakah ada orang lain yang punya ide tentang cara melakukan ini.

Jon Skeets asli, dengan perubahan saya dipotong dengan komentar dalam metode BUILDCOPIER

panggilan untuk ini adalah

        var result = Common.PropertyCopy<POCO>.CopyFrom(Entity);

Kode Jon Skeet asli

/// <summary>
/// Generic class which copies to its target type from a source
/// type specified in the Copy method. The types are specified
/// separately to take advantage of type inference on generic
/// method arguments.
/// http://www.yoda.arachsys.com/csharp/miscutil/
/// </summary>
public static class PropertyCopy<TTarget> where TTarget : class, new()
{
    /// <summary>
    /// Copies all readable properties from the source to a new instance
    /// of TTarget.
    /// </summary>
    public static TTarget CopyFrom<TSource>(TSource source) where TSource : class
    {
        return PropertyCopier<TSource>.Copy(source);
    }

    /// <summary>
    /// Static class to efficiently store the compiled delegate which can
    /// do the copying. We need a bit of work to ensure that exceptions are
    /// appropriately propagated, as the exception is generated at type initialization
    /// time, but we wish it to be thrown as an ArgumentException.
    /// </summary>
    private static class PropertyCopier<TSource> where TSource : class
    {
        private static readonly Func<TSource, TTarget> copier;
        private static readonly Exception initializationException;

        internal static TTarget Copy(TSource source)
        {
            if (initializationException != null)
            {
                throw initializationException;
            }
            if (source == null)
            {
                throw new ArgumentNullException("source");
            }
            return copier(source);
        }

        static PropertyCopier()
        {
            try
            {
                copier = BuildCopier();
                initializationException = null;
            }
            catch (Exception e)
            {
                copier = null;
                initializationException = e;
            }
        }

        private static Func<TSource, TTarget> BuildCopier()
        {
            ParameterExpression sourceParameter = Expression.Parameter(typeof(TSource), "source");
            var bindings = new List<MemberBinding>();
            foreach (PropertyInfo sourceProperty in typeof(TSource).GetProperties())
            {
                if (!sourceProperty.CanRead)
                {
                    continue;
                }
                PropertyInfo targetProperty = typeof(TTarget).GetProperty(sourceProperty.Name);
                if (targetProperty == null)
                {
                    throw new ArgumentException("Property " + sourceProperty.Name + " is not present and accessible in " + typeof(TTarget).FullName);
                }
                if (!targetProperty.CanWrite)
                {
                    throw new ArgumentException("Property " + sourceProperty.Name + " is not writable in " + typeof(TTarget).FullName);
                }

                // THIS IS FALSE FOR SOURCE(INT) TARGET ENUMS
                if (!targetProperty.PropertyType.IsAssignableFrom(sourceProperty.PropertyType))
                {
                    //ADDED FOLLOWING TO HANDLE COPY FROM INT TO ENUM
                    /////////////////////////////////////////////////////////////////////////////////////////////////////
                    // Special Case because Entities are created with property as ints, not enum types
                    if (targetProperty.PropertyType.IsEnum && (sourceProperty.PropertyType == typeof(int)))
                    {
                        var expressionparam = Expression.Parameter(sourceProperty.PropertyType);
                        // cast the entity source as the enum target
                        var cast = Expression.Convert(expressionparam, targetProperty.PropertyType);
                        // add to the binding tree
                        bindings.Add(Expression.Bind(targetProperty, Expression.Property(cast, sourceProperty)));
                        continue;
                    }
                    /////////////////////////////////////////////////////////////////////////////////////////////////////

                    throw new ArgumentException("Property " + sourceProperty.Name + " has an incompatible type in " + typeof(TTarget).FullName);
                }
            Expression initializer = Expression.MemberInit(Expression.New(typeof(TTarget)), bindings);
            return Expression.Lambda<Func<TSource, TTarget>>(initializer, sourceParameter).Compile();
        }
    }
}

enum

public enum NotificationType
{
    InAppNotificiation = 0,
    EmailNotification,
    SMS
}

Kelas Entitas yang dihasilkan oleh EF

public class Entity
{
    public int ProcessedStatus { get; set; }
    public int Priority { get; set; }
    public System.Guid NotifyToUserId { get; set; }
    public string NotifyFrom { get; set; }
    public string NotifySubject { get; set; }
    public string NotifyMessageBody { get; set; }
    public int NotificationType { get; set; }  <-- Stored as int in DB

     public virtual MercuryUser MercuryUser { get; set; } <--complex type
}

Kelas POCO

public class POCO
{
    public int ProcessedStatus { get; set; }
    public int Priority { get; set; }
    public System.Guid NotifyToUserId { get; set; }
    public string NotifyFrom { get; set; }
    public string NotifySubject { get; set; }
    public string NotifyMessageBody { get; set; }
    public NotificationType NotificationType { get; set; }  <-- ENUM TYPE

    public MyUser MyUser { get; set; } <-- complex type
}

Pengecualian dilemparkan ke garis

bindings.Add(Expression.Bind(targetProperty, Expression.Property(cast, sourceProperty)));

Properti 'Int32 NotificationType' tidak ditentukan untuk tipe 'Models.Enums.NotificationType