How to get inner JSON value from JSON without knowing the inner JSON value type name in C#

I have an JSON the object below the scenario, now I need to get only messageNo block obejct only.

{
  "type": {
   "messageNo": 51   
  }
}

Above the scenario, The type is can be change, it can be changed by request. so I need only 开发者_如何学运维typevalue, but the problem is I don't know the type and I need to take this without NewtonSerialization.