public async Task <IHttpActionResult> Put(int id, [FromBody] TodoViewModel viewModel)
{
if (!ModelState.IsValid)
{
return(BadRequest(ModelState));
}
viewModel.UpdateUser = User.Identity.Name;
viewModel.UpdateTime = Now;
viewModel.LastAction = "更新";
var model = Mapper.Map <TodoViewModel, Todo>(viewModel);
_todoRepository.AttachAsModified(model);
await UnitOfWork.SaveChangesAsync();
return(Ok(viewModel));
}