Is there a way match multiple strings to the same enum value when deserializing?

Question

0.00/5 (No votes)

See more:

Hi. I need to deserialize a json with various colour shades to primary colour enums -
Eg. Scarlet and Crimson to enum Red (0), and Teal and Lime to Green (1) - ,but can't work out how , or if it's possible.

The code might look something like this:

using System.Runtime.Serialization;
public enum PrimaryColour
{
     [EnumMember(Value = "Scarlet"), EnumMember(Value = "Crimson")]
     Red = 0,

     [EnumMember(Value = "Teal"), [EnumMember(Value = "lime")]]
     Green=1
}

Any suggestions?

Thanks

Andy

What I have tried:

I've tried varients of the example enum, but all were invalid.

Posted 16-Jul-19 23:19pm

Member 8989123

Updated 17-Jul-19 3:42am

v3

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

phil.o · Answer 1 · 2019-07-17T00:10:00

According to EnumMemberAttribute Class[^], this attribute is defined as:

C#

[AttributeUsage(AttributeTargets.Field, AllowMultiple=false, Inherited=false)]
public sealed class EnumMemberAttribute : Attribute

This means that you cannot match several names to the same enumeration value.
What you can do is provide a method which will return a PrimaryColour value from a string:

C#

public static PrimaryColour GetColour(string value)
{
   switch (value.ToLowerInvariant())
   {
      case "crimson":
      case "scarlet":
         return PrimaryColour.Red;
      case "teal":
      case "lime":
         return PrimaryColour.Green;
      default:
         return PrimaryColour.Black;
   }
}

Then, during the deserialization process, hook it to assign a correct value from json (this part depends on the way the json deserialization is handled, which I have no knowledge of at the moment).

Hope this helps.

Member 8989123 · Answer 2 · 2019-07-17T03:42:00

Thanks for your help, Phil. I can see where you're going with this, but I'm unclear as to how to implement this is the context of reading a file (html get).
Take the following example .This works fine for crimson cars, but I also need scarlet cars to deserialize as Red. Thoughts?

using System;
using System.IO;
using System.Runtime.Serialization;
using Newtonsoft.Json;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            DeserializeObject();
        }

        class CarModel
        {
            public ColourEnum colour;
        }

        enum ColourEnum
        {
            //[EnumMember(Value = "Scarlet")]
            [EnumMember(Value = "Crimson")]
            Red,
            //[EnumMember(Value = "Lime")]
            [EnumMember(Value = "Teal")]
            Green,
        }

        static void DeserializeObject()
        {
            using (Stream reader = new FileStream("c://tmp//test.json", FileMode.Open))
            {
                using (var sr = new StreamReader(reader))
                {

                    using (var jr = new JsonTextReader(sr))
                    {
                        var serializer = new JsonSerializer();
                        CarModel car = serializer.Deserialize<CarModel>(jr);

                        Console.Write(car.colour);
                    }
                }
            }
        }
    }

    /*
    c://tmp//test.json = 

    {
    "colour" : "Crimson"
    }

    */
}

Is there a way match multiple strings to the same enum value when deserializing?

2 solutions

Solution 1

Solution 2

Add your solution here

Preview 0