title: Simple.OData.Client - Unable to invoke Action that accepts entity collection parameter
body: <blockquote>
    <p>I get error "The parameter 'wheels' is of Edm type kind 'Collection'.
    You cannot call CreateCollectionWriter on a parameter that is not of
    Edm type kind 'Collection'."</p>
  </blockquote>
  
  <p>Below are details of my setup:</p>
  
  <p>Web API 2.2 OData v4 service : I have defined Action in WheelsController class in my service like this:</p>
  
  <pre><code>public async Task&lt;IHttpActionResult&gt; UpdateWheels(ODataActionParameters   parameters)
  {
  object value;
  parameters.TryGetValue("carId", out value);
  int carId= (int)value;
  parameters.TryGetValue("wheels", out value)
  IEnumerable&lt;Wheel&gt; wheels = (IEnumerable&lt;Wheel&gt;)value;
  // logic goes here....
  return OK();
  }
  </code></pre>
  
  <p>In WebApiConfig.cs files, the Action configuration is defined as below:</p>
  
  <pre><code>ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
  builder.EntitySet&lt;Car&gt;("Cars");
  builder.EntitySet&lt;Wheel&gt;("Wheels");
  var action = builder.EntityType&lt;Wheel&gt;().Collection.Action("UpdateWheels");
  action.Parameter&lt;int&gt;("carId");
  action.CollectionParameter&lt;Wheel&gt;("wheels");
  </code></pre>
  
  <p><strong>I get success in invoking the above action from RESTClient extenstion in FireFox browser</strong> as POST request to URL "<a href="http://localhost/Service/Wheels/UpdateWheels" rel="nofollow">http://localhost/Service/Wheels/UpdateWheels</a>" with Request Body as </p>
  
  <pre><code>{"carId":2,
  "wheels":[{"Id":1,"Name":"Wheel Front 1","Description":"Front wheel left",   "PositionEnum":"FrontLeft"},
  {"Id":2,"Name":"Wheel Front 2","Description":"Front wheel right",   "PositionEnum":"FrontRight"}]
  }
  </code></pre>
  
  <p>However, it gives <strong>error</strong> when I try to invoke the above service action using Simple.OData.Client in client application such as </p>
  
  <pre><code>public async void TestUpdateWheels(List&lt;Wheel&gt; wheelList)
  {
  // client is derived from ODataClient from assembly Simple.OData.Client.Core.dll, v4.3.0.0
  await client.For&lt;Wheel&gt;()
  .Action("UpdateWheels")
  .Set(new { carId = 2, wheels = wheelList})
  .ExecuteAsync();
  }
  </code></pre>
  
  <blockquote>
    <p>Error message: The parameter 'wheels' is of Edm type kind
    'Collection'. You cannot call CreateCollectionWriter on a parameter
    that is not of Edm type kind 'Collection'.</p>
  </blockquote>
  
  <p>How can I call successfully the above Action from ODataClient?</p>