Serialize and deserialize Enum values as strings

[jasonmead]

Fixes #15

[amccorma]

this issue is not working in the current version. working on a fix to the code.

[amccorma]

   public virtual object DeserializeObject(object value, Type type)
        {
            if (type == null) throw new ArgumentNullException("type");
            string str = value as string;

            if (type == typeof (Guid) && string.IsNullOrEmpty(str))
                return default(Guid);

            if (value == null)
                return null;

            object obj = null;

            if (str != null)
            {
                if (str.Length != 0) // We know it can't be null now.
                {
                    if (type == typeof(DateTime) || (ReflectionUtils.IsNullableType(type) && Nullable.GetUnderlyingType(type) == typeof(DateTime)))
                        return DateTime.ParseExact(str, Iso8601Format, CultureInfo.InvariantCulture, DateTimeStyles.AssumeUniversal | DateTimeStyles.AdjustToUniversal);
                    if (type == typeof(DateTimeOffset) || (ReflectionUtils.IsNullableType(type) && Nullable.GetUnderlyingType(type) == typeof(DateTimeOffset)))
                        return DateTimeOffset.ParseExact(str, Iso8601Format, CultureInfo.InvariantCulture, DateTimeStyles.AssumeUniversal | DateTimeStyles.AdjustToUniversal);
                    if (type == typeof(Guid) || (ReflectionUtils.IsNullableType(type) && Nullable.GetUnderlyingType(type) == typeof(Guid)))
                        return new Guid(str);
                    if (type == typeof(Uri))
                    {
                        bool isValid =  Uri.IsWellFormedUriString(str, UriKind.RelativeOrAbsolute);

                        Uri result;
                        if (isValid && Uri.TryCreate(str, UriKind.RelativeOrAbsolute, out result))
                            return result;

                                                return null;
                    }

                                    if (type == typeof(string))  
                                        return str;

                                    return Convert.ChangeType(str, type, CultureInfo.InvariantCulture);
                }
                else
                {
                    if (type == typeof(Guid))
                        obj = default(Guid);
                    else if (ReflectionUtils.IsNullableType(type) && Nullable.GetUnderlyingType(type) == typeof(Guid))
                        obj = null;
                    else
                        obj = str;
                }
                // Empty string case
                if (!ReflectionUtils.IsNullableType(type) && Nullable.GetUnderlyingType(type) == typeof(Guid))
                    return str;
            }
            else if (value is bool)
                return value;

            bool valueIsLong = value is long;
            bool valueIsDouble = value is double;
            if (type.IsEnum)
            {
                if (value is double || value is int || value is long)
                {
                    return Enum.ToObject(type, Convert.ToInt32(value.ToString()));
                }
                else if (value is string)
                {
                    return Enum.Parse(type, value.ToString());
                }
            }
            if ((valueIsLong && type == typeof(long)) || (valueIsDouble && type == typeof(double)))
                return value;
            if ((valueIsDouble && type != typeof(double)) || (valueIsLong && type != typeof(long)))
            {
                obj = type == typeof(int) || type == typeof(long) || type == typeof(double) || type == typeof(float) || type == typeof(bool) || type == typeof(decimal) || type == typeof(byte) || type == typeof(short)
                            ? Convert.ChangeType(value, type, CultureInfo.InvariantCulture)
                            : value;
            }
            else
            {
                IDictionary<string, object> objects = value as IDictionary<string, object>;
                if (objects != null)
                {
                    IDictionary<string, object> jsonObject = objects;

                    if (ReflectionUtils.IsTypeDictionary(type))
                    {
                        // if dictionary then
                        Type[] types = ReflectionUtils.GetGenericTypeArguments(type);
                        Type keyType = types[0];
                        Type valueType = types[1];

                        Type genericType = typeof(Dictionary<,>).MakeGenericType(keyType, valueType);

                        IDictionary dict = (IDictionary)ConstructorCache[genericType]();

                        foreach (KeyValuePair<string, object> kvp in jsonObject)
                            dict.Add(kvp.Key, DeserializeObject(kvp.Value, valueType));

                        obj = dict;
                    }
                    else
                    {
                        if (type == typeof(object))
                            obj = value;
                        else
                        {
                            obj = ConstructorCache[type]();
                            foreach (KeyValuePair<string, KeyValuePair<Type, ReflectionUtils.SetDelegate>> setter in SetCache[type])
                            {
                                object jsonValue;
                                if (jsonObject.TryGetValue(setter.Key, out jsonValue))
                                {
                                    jsonValue = DeserializeObject(jsonValue, setter.Value.Key);
                                    setter.Value.Value(obj, jsonValue);
                                }
                            }
                        }
                    }
                }
                else
                {
                    IList<object> valueAsList = value as IList<object>;
                    if (valueAsList != null)
                    {
                        IList<object> jsonObject = valueAsList;
                        IList list = null;

                        if (type.IsArray)
                        {
                            list = (IList)ConstructorCache[type](jsonObject.Count);
                            int i = 0;
                            foreach (object o in jsonObject)
                                list[i++] = DeserializeObject(o, type.GetElementType());
                        }
                        else if (ReflectionUtils.IsTypeGenericeCollectionInterface(type) || ReflectionUtils.IsAssignableFrom(typeof(IList), type))
                        {
                            Type innerType = ReflectionUtils.GetGenericListElementType(type);
                            list = (IList)(ConstructorCache[type] ?? ConstructorCache[typeof(List<>).MakeGenericType(innerType)])(jsonObject.Count);
                            foreach (object o in jsonObject)
                                list.Add(DeserializeObject(o, innerType));
                        }
                        obj = list;
                    }
                }
                return obj;
            }
            if (ReflectionUtils.IsNullableType(type))
                return ReflectionUtils.ToNullableType(obj, type);
            return obj;
        }

[amccorma]

Here the code change:

Method:

* public virtual object DeserializeObject(object value, Type type)*

line: 1386

Current version at time of change is 0.38.0
or copy method above and replace. tested with 4 enums.

 if (type.IsEnum)
            {
                if (value is double || value is int || value is long)
                {
                    return Enum.ToObject(type, Convert.ToInt32(value.ToString()));
                }
                else if (value is string)
                {
                    return Enum.Parse(type, value.ToString());
                }
            }

[jasonmead]

Submit a PR with tests, please.

[amccorma]

I have never done a PR request. reading up on google and going try it.

[amccorma]

I followed this: https://guides.github.com/activities/contributing-to-open-source/

I did the fork. made a branch (enumfix). compiled solution. updated source. committed branch. added tests (EnumTest). unsure what do to next. the code been committed to the branch.

Everything compiles. test worked ok. checked in.

[jasonmead]

The next step would be to open a pull request from your forked branch.

[jchannon]

@jasonmead this is great, i'm not sure what the diff between your PR and @amccorma PR #72 although that PR I think has line ending issues as the whole simplejson file has changed. I'd like to get this into Nancy https://github.com/NancyFx/Nancy for the JSON work you did.

Including @prabirshrestha in this too.

What needs to be done to get this feature in ASAP?

[jasonmead]

This will have to be implemented in Nancy directly. Unfortunately, we had to modify SimpleJson.cs in Nancy to get it to work correctly.

[prabirshrestha]

@jchannon I will be out of town. will have to look at this next week.

[Deepscorn]

What is the status? I need enum support to use SimpleJson in a Unity game (last stable version of which sadly provides us, programmers, with C# 4 and .NET 2.0-3.5 at the time of writing which don't make much of choise when handling json). It's the only thing, that stops me from using SimpleJson. I need something like this to work:

[DataContract]
    public enum Keeper
    {
        [DataMember(Name = "no keeper")]
        None,
        [DataMember(Name = "Mary Rose")]
        Mary,
        [DataMember(Name = "Tom The Third")]
        Tom,
        [DataMember(Name = "Simply, Todd")]
        Todd
    }

[DataContract]
    public class Animal : JsonResponse
    {
        [NotNull]
        [DataMember(Name = "animal color")] // works ok
        public string Color { get; private set; }
        
        [DataMember(Name = "animal keeper")] // fails, enum serialized as number ( 0 for None, 1 for Mary and so on)
        public Keeper Keeper { get; private set; }
}

So, needed serialized example of animal:
{ "animal color" : "red", "animal keeper" : "Mary Rose" }

Actual serialized example of animal:
{ "animal color" : "red", "animal keeper" : 1 }

I came from java and there we successfully used (for example) com.google.api.client.util.Value attribute to specify [de]serialized string value for each enum member:

public enum CardStatus {
    @Value("active")
    ACTIVE,
    @Value("expired")
    EXPIRED,
    @Value("blocked")
    BLOCKED
}

public class Card {
    @Key("card id")
    private String id;
    @Key("status")
    private CardStatus status;
}

So, serialized example of Card:
{ "card id" : "101010", "status" : "expired" }

PS com.google.api.client.util.Value is in com.google.http-client:google-http-client-android:1.22.0 or com.google.http-client:google-http-client-jackson2:1.22.0 - don't remember exactly, allways imported both at the same time

PS I tested code of that merge request and it gave me:
{ "animal color" : "red", "animal keeper" : "Mary" }
As you see, sadly, DataMember attribute ignored