JsonToParametersAttribute

file.cs

public class JsonToParametersAttribute : ActionFilterAttribute
        {
            public override void OnActionExecuting(ActionExecutingContext filterContext)
            {
                base.OnActionExecuting(filterContext);

                var stream = filterContext.HttpContext.Request.Body;
                using (var sr = new StreamReader(stream))
                using (var jsonTextReader = new JsonTextReader(sr))
                {
                    var serializer = new JsonSerializer();
                    var body = serializer.Deserialize<JObject>(jsonTextReader);

                    if (body == null) return;

                    foreach (var parameter in filterContext.ActionDescriptor.Parameters)
                    {
                        var jsonProperty = body.Properties().SingleOrDefault(p => p.Name == parameter.Name);
                    
                        if (jsonProperty != null)
                        {
                            var param = filterContext.ActionDescriptor.Parameters.OfType<ControllerParameterDescriptor>().FirstOrDefault(e => e.Name == parameter.Name);

                            if (param == null)
                            {
                                continue;
                            }

                            if (!filterContext.ActionArguments.ContainsKey(parameter.Name))
                            {
                                object value;

                                try
                                {
                                    value = jsonProperty.Value.ToObject(param.ParameterInfo.ParameterType);
                                }
                                catch (Exception)
                                {
                                    value = GetDefault(param.ParameterInfo.ParameterType);
                                }

                                filterContext.ActionArguments.Add(parameter.Name, value);
                            }
                        }
                    }
                }
            }
            private static object GetDefault(Type type)
            {
                if (type.IsValueType)
                {
                    return Activator.CreateInstance(type);
                }
                return null;
            }
    }