private void ValidateResourceTechnolgies(ResourceTechnologiesAddViewModel viewModel)
{
if (ModelState.IsValidField("ResourceId") &&
ModelState.IsValidField("TechnologyId"))
{
if (_resourcesRepository.ResourceHasTechnologyAlready(viewModel.ResourceId, viewModel.TechnologyId))
{
ModelState.AddModelError("TechnologyId",
"This technology already exists for this resource.");
}
}
}