serialization of enum results in int

Question

When i do a GET request to retrieve my list of Persons the enums(Title) get converted into integers:


class Person {

public Title PersonTitle{ get; set;}
public string Name { get; set;}


}

enum Title {
   STUDENT,
   TEACHER,
   DIRECTOR
}

Let's Say we have the following situation:

Person first = new Person(){
  PersonTitle = Title.STUDENT,
  Name = "Dave"
}

this wil result in the following JSON:

[
 {
   "Name" : "Dave",
   "PersonTitle" : 1,
 }
]

How do I get the real value of the enum (STUDENT in this case) ?

I forgot the name of the property but that's not the problem. It's edited now — schweppes0x, Oct 26 '21 at 13:29
An enum *is* an integer. An enum value is By default enums are serialized as integers. Both JSON.NET and System.Text.Json can be configured to serialize them using their tag names instead. Which one are you using? For System.Text.Json check [Enums as strings](https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json-customize-properties?pivots=dotnet-5-0#enums-as-strings) — Panagiotis Kanavos, Oct 26 '21 at 13:32
When i do a Get request, my method sends a list with those persons. — schweppes0x, Oct 26 '21 at 13:47

schweppes0x · Accepted Answer · 2021-11-01T07:24:45.207

2

The only code that had to be changed was:

Before :

public enum Title {
   STUDENT,
   TEACHER,
   DIRECTOR
}

After :

using using System.Text.Json.Serialization;
[JsonConverter(typeof(JsonStringEnumConverter))]
public enum Title {
   STUDENT,
   TEACHER,
   DIRECTOR
}

Now the response looks like:


[
 {
   "Name" : "Dave",
   "PersonTitle" : "Student",
 }
]

edited Nov 01 '21 at 07:24

answered Nov 01 '21 at 07:14

schweppes0x

182
1
13

huMpty duMpty · Answer 2 · 2021-10-27T09:16:03.057

0

you can set the JsonConverterAttribute

class Person {

[JsonConverter(typeof(StringEnumConverter))]
public Title PersonTitle{ get; set;}
public string Name { get; set;}


}

Updating Enum with EnumMemberAttribute

enum Title {
   [EnumMember(Value = "Student")]
   STUDENT,
   [EnumMember(Value = "Teacher")]
   TEACHER,
   [EnumMember(Value = "Director")]
   DIRECTOR
}

edited Oct 27 '21 at 09:16

answered Oct 26 '21 at 13:32

huMpty duMpty

14,346
14
60
99

I get: InvalidOperationException: The converter specified on 'MyClass.Person.FileType' does not derive from JsonConverter or have a public parameterless constructor. – schweppes0x Oct 26 '21 at 13:42
@schweppes0x Are you using newtonsoft or System.Text? – huMpty duMpty Oct 26 '21 at 15:17
Newtonsoft and I am not sure why but now I am not getting any error but the JSON is still not correct and still displays integers. – schweppes0x Oct 27 '21 at 05:48
@schweppes0x: can you try adding [EnumMember](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.serialization.enummemberattribute?view=net-5.0) i.e `[EnumMember(Value = "Student")]` – huMpty duMpty Oct 27 '21 at 07:35
but the value is unknown so maybe the Value is teacher and not student – schweppes0x Oct 27 '21 at 08:31
@schweppes0x: What you mean by *"value is unknown"*? What I meant is to decorate the enum with EnumMember. Have you tried doing it? – huMpty duMpty Oct 27 '21 at 09:14
I tried it and sadly it does not work. – schweppes0x Oct 27 '21 at 09:55

Ivo · Answer 3 · 2021-10-26T13:40:01.417

0

You need to add the adequate converter to the JSON serializer.

System.Text.Json:

Use JsonStringEnumConverter class.

Json.NET:

Use StringEnumConverter class.

edited Oct 26 '21 at 13:40

answered Oct 26 '21 at 13:33

Ivo

396
1
9

serialization of enum results in int

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