How to rename an inherited API member in a subclass?

Question

Say I have:

public class Parent{
    [ApiMember(Name = "parentItem")]
    public string Item {get; set;}
}

and

public class Child : Parent {
    [ApiMember(Name = "childItem")]
    public new string Item {get; set;}
}

Since the 'Item' property in the parent class should be hidden, why does making a request with {"childItem": "something"} returns Could not find property childItem on RequestObject? That said, what is the best way (or is there a way) to rename inherited API members/properties in the subclass?

[Related reading](https://stackoverflow.com/questions/1399127/difference-between-new-and-override) — ProgrammingLlama, Oct 30 '18 at 00:43

score 3 · Accepted Answer · answered Oct 30 '18 at 12:12

[DataContract] and [DataMember] attributes affect serialization where as [Api*] attributes are only used to document and add extra metadata about your API, but it doesn't affect serialization behavior.

So you should instead change your DTOs to:

[DataContract]
public class Parent
{
    [DataMember(Name = "parentItem")]
    public virtual string Item { get; set; }
}

[DataContract]
public class Child : Parent 
{
    [DataMember(Name = "childItem")]
    public override string Item { get; set; }
}

Where they will be used when serializing in most of ServiceStack's serializers, e.g:

var json1 = new Parent { Item = "parent" }.ToJson();
json1.Print();

var json2 = new Child { Item = "child" }.ToJson();
json2.Print();

Which outputs:

{"parentItem":"parent"}
{"childItem":"child"}

You can try this example Live on Gistlyn.

score 1 · Answer 2 · answered Oct 30 '18 at 00:42

1

Try making the property virtual in the parent and then simply override it (without new keyword) in the child class like that:

public class Parent{
    [ApiMember(Name = "parentItem")]
    public virtual string Item {get; set;}
}

public class Child : Parent {
    [ApiMember(Name = "childItem")]
    public override string Item {get; set;}
}

answered Oct 30 '18 at 00:42

Szab

1,263
8
18

I tried to do `public override string Item {get; set;} = "test default"` and I can see that the property is properly overriden as when I debug it, I can see the default value "test default". However, making a request with `{"childItem": "something"}` still returns `Could not find property childItem on RequestObject`. – natasha Oct 30 '18 at 01:03
Please post more code, e.g. a controller that's supposed to handle the request. – Szab Oct 30 '18 at 07:31

How to rename an inherited API member in a subclass?

2 Answers2