Override field name deserialization in ServiceStack

Question

I'm using ServiceStack to deserialize some HTML form values but can't figure out how to override the value that each field should be read from.

For example, the form posts a value to first_name but the property on my POCO is called FirstName. how would I do mapping like that in ServiceStack

mythz · Accepted Answer · 2019-04-01T13:10:33.960

36

The ServiceStack Text serializers support [DataMember] aliases where you can use the Name parameter to specify what alias each field should be, e.g:

[DataContract]
public class Customer
{
    [DataMember(Name="first_name")]
    public string FirstName { get; set; }

    [DataMember(Name="last_name")]
    public string LastName { get; set; }
}

Note: Once you add [DataContract] / [DataMember] attributes to your DTOs then the behavior becomes opt-in and you will have add [DataMember] on each of the properties you want serialized.

Emitting idiomatic JSON for all DTOs

You can instruct JSON serialization to follow a different convention by specifying the following global settings:

//Emit {"firstName":"first","lastName":"last"}
JsConfig.Init(new Config { TextCase = TextCase.CamelCase });

//Emit {"first_name":"first","last_name":"last"}
JsConfig.Init(new Config { TextCase = TextCase.SnakeCase });

edited Apr 01 '19 at 13:10

answered Apr 11 '12 at 21:23

mythz

141,670
29
246
390

I've tried that and I don't see that opt-in behaviour either, it seems like service stack completely ignores the DataContract/Member Attribute. I'm using the attributes in System.Runtime.Serialization. – kay.one Apr 11 '12 at 21:32
1

Ok this works for ServiceStack's JSON and JSV text serializers, I've just commited the change where the above also works for the QueryString and HTML Form POST parsing routine at: https://github.com/ServiceStack/ServiceStack/commit/e1d48d9d7e9e17c506e3759bfd0712cbad58280d - available on next release of ServiceStack on NuGet in a few days. You can use JSON or Request model binder in the meantime https://github.com/ServiceStack/ServiceStack/wiki/Serialization-deserialization – mythz Apr 11 '12 at 21:49
Is [DataContract] still the only way to customize the Property Name? As its not optimal when applying on a Base class, in a POCO env. – Daniel Halan Aug 30 '14 at 15:35
@mythz - The [documentation](https://github.com/ServiceStack/ServiceStack.Text) says, "At the moment it is not possible to customize the Property Name." May I assume that line in the documentation is out of date? – dbc May 04 '15 at 06:35

score 5 · Answer 2 · edited May 23 '17 at 12:31

In order to serialise C# class with underscore convention, you need to set JsConfig.EmitLowercaseUnderscoreNames to true as mythz said.

JsConfig.EmitLowercaseUnderscoreNames = true;

But, in my experience, Deserialising would fail, as it expect CamelCased values. To enable underscore json value deserialisation, you need to set JsConfig's PropertyConvention.

JsConfig.PropertyConvention = PropertyConvention.Lenient;

I use a simple helper method to resolve the serialisation and deserialisation issue.

public static class JsonHelpers
{
    public static string ToUnderscoredJson<T>(this T obj)
    {
        JsConfig.EmitLowercaseUnderscoreNames = true;

        return JsConfig.PreferInterfaces
            ? JsonSerializer.SerializeToString(obj, AssemblyUtils.MainInterface<T>())
            : JsonSerializer.SerializeToString(obj);
    }

    public static T FromUnderscoredJson<T>(this string json)
    {
        JsConfig.PropertyConvention = PropertyConvention.Lenient;
        return JsonSerializer.DeserializeFromString<T>(json);
    }
}

Override field name deserialization in ServiceStack

2 Answers2

Emitting idiomatic JSON for all DTOs

Linked