c# - Ignoring class members that throw exceptions when serializing to JSON

Question

I'm using the Newtonsoft JSON serializer and it works for most objects.

Unfortunately I get a JsonSerializationException when I try to serialize a large object, one of whose members throws a NullReferenceException.

Is there anyway to ignore the offending member and serialize the rest of the object?

I'm thinking perhaps in the JsonSerializerSettings?

Here's a simplified version of what I want to do:

private class TestExceptionThrowingClass
{
    public string Name { get { return "The Name"; } }
    public string Address { get { throw new NullReferenceException(); } }
    public int Age { get { return 30; } }
}

[Test]
public void CanSerializeAClassWithAnExceptionThrowingMember()
{ 
    // Arrange
    var toSerialize = new TestExceptionThrowingClass();

    // Act

    var serializerSettings = new Newtonsoft.Json.JsonSerializerSettings();
    serializerSettings.MaxDepth = 5;
    serializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
    serializerSettings.MissingMemberHandling = Newtonsoft.Json.MissingMemberHandling.Ignore;
    serializerSettings.NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore;
    serializerSettings.ObjectCreationHandling = Newtonsoft.Json.ObjectCreationHandling.Reuse;
    serializerSettings.DefaultValueHandling = Newtonsoft.Json.DefaultValueHandling.Ignore;

    var result = Newtonsoft.Json.JsonConvert.SerializeObject(toSerialize);

    // Assert
    Assert.That(result, Is.EqualTo(@"{""Name"":""The Name"",""Age"":30}"));
}

And here's the stack trace:

at Newtonsoft.Json.Serialization.DynamicValueProvider.GetValue(Object target) 
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CalculatePropertyValues(JsonWriter writer, Object value, JsonContainerContract contract, JsonProperty member, JsonProperty property, JsonContract& memberContract, Object& memberValue) 
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty) 
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue(JsonWriter writer, Object value, JsonContract valueContract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerProperty) 
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize(JsonWriter jsonWriter, Object value, Type objectType) 
at Newtonsoft.Json.JsonSerializer.SerializeInternal(JsonWriter jsonWriter, Object value, Type objectType) 
at Newtonsoft.Json.JsonConvert.SerializeObject(Object value, Type type, Formatting formatting, JsonSerializerSettings settings) 
at Newtonsoft.Json.JsonConvert.SerializeObject(Object value) 
at AspectsProject.Aspects.CachingPolicy.CachingPolicyCacheKeyCreatorTests.CanSerializeAClassWithAnExceptionThrowingMember() in D:Devest.cs:line 169
    --NullReferenceException 
at AspectsProject.Aspects.CachingPolicy.CachingPolicyCacheKeyCreatorTests.TestExceptionThrowingClass.get_Address() in D:Devest.cs:line 149 
at GetAddress(Object ) 
at Newtonsoft.Json.Serialization.DynamicValueProvider.GetValue(Object target)

I'm happy to use a different JSON serializer if someone knows one that will do this.

Answer 1

A simpler way to ignore errors:

JsonSerializerSettings settings = new JsonSerializerSettings();
settings.Error = (serializer,err) => {
    err.ErrorContext.Handled = true;
}

or

settings.Error = (serializer,err) => err.ErrorContext.Handled = true;