// Command to delete the material public void deleteMaterial(int materialId) { // Delete the material from the database MaterialModel.deleteMaterial(materialId); // Remove the material from the deleted material list MaterialModel deletedMaterial = materialList.Where(mat => mat.materialId == materialId).First(); // Remove from the active material list materialList.Remove(deletedMaterial); originalMaterialList.Remove(deletedMaterial); // Add to the deleted material list deletedMaterialList.Add(deletedMaterial); }