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No parameterless constructor defined for this object on arrays & enumerables of simple types

See original GitHub issue

The following error is thrown when Execute<T>() is called with T having string[], IEnumerable<T> and similar.

This seems rather easy to fix on the JsonDeserializer, I wonder if it wasn’t done on purpose?

Let me know if I should send a PR with a fix

System.MissingMethodException: No parameterless constructor defined for this object.
   at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck)
   at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)
   at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)
   at System.Activator.CreateInstance(Type type, Boolean nonPublic)
   at System.Activator.CreateInstance(Type type)
   at RestSharp.Deserializers.JsonDeserializer.CreateAndMap(Type type, Object element)
   at RestSharp.Deserializers.JsonDeserializer.ConvertValue(Type type, Object value)
   at RestSharp.Deserializers.JsonDeserializer.Map(Object target, IDictionary`2 data)
   at RestSharp.Deserializers.JsonDeserializer.CreateAndMap(Type type, Object element)
   at RestSharp.Deserializers.JsonDeserializer.ConvertValue(Type type, Object value)
   at RestSharp.Deserializers.JsonDeserializer.Map(Object target, IDictionary`2 data)
   at RestSharp.Deserializers.JsonDeserializer.CreateAndMap(Type type, Object element)
   at RestSharp.Deserializers.JsonDeserializer.ConvertValue(Type type, Object value)
   at RestSharp.Deserializers.JsonDeserializer.BuildList(Type type, Object parent)
   at RestSharp.Deserializers.JsonDeserializer.ConvertValue(Type type, Object value)
   at RestSharp.Deserializers.JsonDeserializer.Map(Object target, IDictionary`2 data)
   at RestSharp.Deserializers.JsonDeserializer.CreateAndMap(Type type, Object element)
   at RestSharp.Deserializers.JsonDeserializer.ConvertValue(Type type, Object value)
   at RestSharp.Deserializers.JsonDeserializer.Map(Object target, IDictionary`2 data)
   at RestSharp.Deserializers.JsonDeserializer.Deserialize[T](IRestResponse response)
   at RestSharp.RestClient.Deserialize[T](IRestRequest request, IRestResponse raw)

Issue Analytics

State:
Created 9 years ago
Comments:16 (3 by maintainers)

Top GitHub Comments

17reactions

nadirakdagcommented, Jan 3, 2015

this error about arrays if you convert your arrays to list you can escape this error. First version public object[] sizes { get; set; }

Right version public List<object> sizes { get; set; }

11reactions

urigcommented, Sep 9, 2015

+1 for including this feature in the built-in JSON deserializer.

Deserializing arrays is a basic scenario for consuming REST APIs. IMHO RestSharp users, especially inexperienced ones, should not have to invest effort in custom serialization for something so trivial.