why In web api returning an entity that has a one to many relationship causes an error?

Question

Guys I have a One to many relation to same class called user,
I am returning one instance of user in web apis get method it works fine as far as I don\'t have any

Answer 1

Try to change webApi formatter. Add these lines in WebApiConfig.cs:

var json = config.Formatters.JsonFormatter;
json.SerializerSettings.PreserveReferencesHandling = Newtonsoft.Json.PreserveReferencesHandling.Objects;
config.Formatters.Remove(config.Formatters.XmlFormatter);

And add this line:

json.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore

Answer 2

Apply the [JsonIgnore] attribute to the navigation property you don't want to be serialised. It will still serialise both the parent and child entities but just avoids the self referencing loop.