protected override void buttonEdit_Click(object sender, EventArgs e)
        {
            TId index = GetSelectedEntityId();

            if (index != -1)
            {
                EditConstraintForm editForm = new EditConstraintForm(ModelStorage.Instance.Model.FunctionalConstraints[index]);
                EditEntity(editForm, ModelStorage.Instance.Model.FunctionalConstraints, index);
            }
        }
        protected override void buttonAdd_Click(object sender, EventArgs e)
        {
            EditConstraintForm addForm = new EditConstraintForm();

            AddEntity(addForm, ModelStorage.Instance.Model.FunctionalConstraints);
        }