public IActionResult Show(string?command) { var modelData = _modelService.GetAll(); if (command == "Addition") { modelData = _modelService.GetAll().Where(x => x.Operation == "Addition").ToList(); } if (command == "Substract") { modelData = _modelService.GetAll().Where(x => x.Operation == "Substract").ToList(); } if (command == "Multiply") { modelData = _modelService.GetAll().Where(x => x.Operation == "Multiply").ToList(); } if (command == "Divide") { modelData = _modelService.GetAll().Where(x => x.Operation == "Divide").ToList(); } if (command == "Modulo") { modelData = _modelService.GetAll().Where(x => x.Operation == "Modulo").ToList(); } if (command == "All") { modelData = _modelService.GetAll(); } return(View(modelData)); }