public async Task <HttpResponseMessage> CheckUserNameAndEmailExistence(string email, string userName) { if (!ModelState.IsValid) { return(Request.CreateResponse(HttpStatusCode.BadRequest)); } registerManager = new RegisterManager(); var isEmailExist = await registerManager.CheckEmailExistence(email); var isuserNameExist = await registerManager.CheckUserNameExistence(userName); bool[] existence = { isEmailExist, isuserNameExist }; return(Request.CreateResponse(HttpStatusCode.OK, existence)); }