private void button4_Click(object sender, EventArgs e) { if (MessageBox.Show("是否删除该产品类型?", "提示", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes) { if (db.DeleteCategory(int.Parse(lbCategory.SelectedValue.ToString())) == -1) { MessageBox.Show("删除失败,该产品类型已被使用!"); return; } FormSetting_Load(sender, e); } }