C#商品信息修改失败,添加和删除都成功


 private void button1_Click_2(object sender, EventArgs e)
        {
            string id = textBox2.Text.Trim();
            string name = textBox1.Text.Trim();
            string price = textBox4.Text.Trim();
            string spec = textBox3.Text.Trim();
            string remark = textBox5.Text.Trim();
            string supplier = comboBox1.Text.Trim();
            string connStr = "server=mayu;database=FreshMarket;Integrated Security=True";
            SqlConnection conn = new SqlConnection(connStr);
            conn.Open();
            string sqlStr = "update goods1 set name=@name, price=@price,spec=@spec, remark=@remark where id=@id";
           SqlCommand cmd = new SqlCommand(sqlStr, conn);
            // SQL字符串参数赋值
            cmd.Parameters.Add(new SqlParameter("@id", id));
            cmd.Parameters.Add(new SqlParameter("@name", name));
            cmd.Parameters.Add(new SqlParameter("@price", price));
            cmd.Parameters.Add(new SqlParameter("@spec", spec));
            cmd.Parameters.Add(new SqlParameter("@remark", remark));

            // 将命令发送给数据库
            int res = cmd.ExecuteNonQuery();
          
            // 根据返回值判断是否修改成功
            if (res != 0)
            {
                MessageBox.Show("商品信息修改成功");
                this.Close();
            }
            else
            {
                MessageBox.Show("商品信息修改失败");
            }
 conn.Close();

修改不成功