Configure Sqlite.net for saving NodaTime as blob

initSqlite.fs

let extraTypeMappings = new Dictionary<Type, string>()
        
extraTypeMappings.Add(typeof<NodaTime.LocalDate>, "blob")
extraTypeMappings.Add(typeof<NodaTime.OffsetDateTime>, "blob")
extraTypeMappings.Add(typeof<NodaTime.Duration>, "blob")

let sqlConnection = new SQLiteConnection(sqlitePlatform, 
                                            databaseFilePath, 
                                            false,
                                            NodaTypeSerializerDelegate.Delegate(),
                                            null,
                                            extraTypeMappings
                                            )

NodaTypeSerializerDelegate.fs

module NodaTypeSerializerDelegate =

    let localDateType = typeof<LocalDate>
    let offsetDateTimeType = typeof<OffsetDateTime>
    let durationType = typeof<Duration>

    let supportedTypes = [
        (localDateType);
        (offsetDateTimeType);
        (durationType)
        ]

    let getSupportedType typ =
        supportedTypes
        |> List.filter (fun i -> i = typ)
        |> List.tryHead

    let canSerialize (typ : Type) =
        let supportedTyp = getSupportedType typ

        match supportedTyp with
        | Some x ->
            true
        | _ ->
            false

    

    let serialize (obj : Object) =
        
        let typ = obj.GetType()
        
        let mutable formatResult = ""

        if typ = localDateType then
            formatResult <- LocalDatePattern.IsoPattern.Format (obj :?> LocalDate)

        if typ = offsetDateTimeType then
            formatResult <- OffsetDateTimePattern.ExtendedIsoPattern.Format (obj :?> OffsetDateTime)
            
        if typ = durationType then
            formatResult <- DurationPattern.RoundtripPattern.Format (obj :?> Duration)
            
        System.Text.Encoding.Unicode.GetBytes formatResult

        
    let deserialize (data : byte[]) (typ : Type) : Object =
        let text = System.Text.Encoding.Unicode.GetString(data, 0, data.Length)

        let mutable result : Object = null

        if typ = localDateType then
            let parseResult = LocalDatePattern.IsoPattern.Parse text
            result <- parseResult.Value :> Object

        if typ = offsetDateTimeType then
            let parseResult = OffsetDateTimePattern.ExtendedIsoPattern.Parse text
            result <- parseResult.Value :> Object

        if typ = durationType then
            let parseResult = DurationPattern.RoundtripPattern.Parse text
            result <- parseResult.Value :> Object

        result
        

    let Delegate() =
        new BlobSerializerDelegate(new BlobSerializerDelegate.SerializeDelegate(serialize),
                                   new BlobSerializerDelegate.DeserializeDelegate(deserialize),
                                   new BlobSerializerDelegate.CanSerializeDelegate(canSerialize))