Unity WebRequest Custom

public enum MyHttpVerb { POST, GET, CREATE, DELETE, PUT, HEAD }
public class MyUnityWebRequest : UnityWebRequest
{
    static Dictionary<MyHttpVerb, string> dePara =
        new Dictionary<MyHttpVerb, string>()
    {
        [MyHttpVerb.POST] = kHttpVerbPOST,
        [MyHttpVerb.GET] = kHttpVerbGET,
        [MyHttpVerb.CREATE] = kHttpVerbCREATE,
        [MyHttpVerb.DELETE] = kHttpVerbDELETE,
        [MyHttpVerb.PUT] = kHttpVerbPUT,
        [MyHttpVerb.HEAD] = kHttpVerbHEAD,
    };

    public MyUnityWebRequest(Uri uri, MyHttpVerb method) : base(uri, dePara[method]) { }
    public MyUnityWebRequest(string uri, MyHttpVerb method) : base(uri, dePara[method]) { }

}

public class Xablau : MonoBehaviour
{
    void Start()
    {
        using (var webRequest = new MyUnityWebRequest("http://example.com",MyHttpVerb.POST))
        {
            // le o request
        }
    }
}