开发“航班查询及预定”系统

整体的首页

//创建配适器
        SqlDataAdapter sa;
        //创建临时数据集
        DataSet ds;
        public FrmLogin()
        {
            InitializeComponent();
        }

        private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
        {
            //创建连接对象
            SqlConnection conn = new SqlConnection(DBHelper.str);
        }

        private void FrmLogin_Load(object sender, EventArgs e)
        {
            //调用出发地的显示信息
            add();
            //调用到达目的地的显示信息
            Goto();
        }
        /// <summary>
        /// 显示出发地的信息
        /// </summary>
        public void add()
        {
            //连接对象
            SqlConnection conn = new SqlConnection(DBHelper.str);
            //拼接sql语句
            string sql = "select * from CityInfo";
            //适配器
            sa = new SqlDataAdapter(sql, conn);
            //创建数据集字符串
            ds = new DataSet();
            //填充数据集

            sa.Fill(ds);
            //向数据集和中添加文字
            //Tables获取包含DataSet中的集合
            DataRow row = ds.Tables[0].NewRow();
            row["Id"] = -1;
            row["CityName"] = "请选择";
            ds.Tables[0].Rows.InsertAt(row, 0);
            //获取或者设置文本框的数据源
            cmbGo.DataSource = ds.Tables[0];
            //显示属性
            cmbGo.DisplayMember = "CityName";
            //真实属性
            cmbGo.ValueMember = "Id";
            cmbGo.DataSource = ds.Tables[0];//绑定数据源
        }

        /// <summary>
        /// 显示目的地的信息
        /// </summary>
        public void Goto()
        {
            //连接对象
            SqlConnection conn = new SqlConnection(DBHelper.str);
            //拼接sql语句
            string sql = "select * from CityInfo";
            //适配器
            sa = new SqlDataAdapter(sql, conn);
            //创建数据集字符串
            ds = new DataSet();
            //填充数据集

            sa.Fill(ds);
            //向数据集和中添加文字
            //Tables获取包含DataSet中的集合
            DataRow row = ds.Tables[0].NewRow();
            row["Id"] = -1;
            row["CityName"] = "请选择";
            ds.Tables[0].Rows.InsertAt(row, 0);
            //获取或者设置文本框的数据源
            cmbBourn.DataSource = ds.Tables[0];
            //显示属性
            cmbBourn.DisplayMember = "CityName";
            //真实属性
            cmbBourn.ValueMember = "Id";
            cmbBourn.DataSource = ds.Tables[0];//绑定数据源
        }
        /// <summary>
        /// 查询按钮把数据库的信息显示到DataGridView中
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnRefer_Click(object sender, EventArgs e)
        {
            //创建连接对象
            SqlConnection conn = new SqlConnection(DBHelper.str);
            try
            {
                int grade = Convert.ToInt32(cmbBourn.SelectedValue);
                int grade1 = Convert.ToInt32(cmbGo.SelectedValue);
                //拼接sql语句
                string sql = @"select f.FlightNO,a.Airways,f.LeaveTime,f.LandTime,f.Price 
               from FlightInfo as f,AirwaysInfo as a 
               where f.AirwaysId = a.Id and f.LeaveCity ='" + grade + "' and f.Destination = '" + grade1 + "'";

                ds = new DataSet();
                sa = new SqlDataAdapter(sql, conn);
                sa.Fill(ds);//填充数据
                dataGridView1.DataSource = ds.Tables[0];//绑定数据源
            }
                
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                
            }
        }



        /// <summary>
        /// 将单元格的值显示在文本框中
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void dataGridView1_CellContentClick_1(object sender, DataGridViewCellEventArgs e)
        {
            dataGridView1.AutoGenerateColumns = false;
            //在第二个分组框显示信息
            //拿到当前选中项的航班号
            string Flightnum = Convert.ToString(dataGridView1.SelectedRows[0].Cells[0].Value);            //航空公司
            string Airways = Convert.ToString(dataGridView1.SelectedRows[0].Cells[1].Value);
            //出发时间
            string LeaveTime = Convert.ToString(dataGridView1.SelectedRows[0].Cells[2].Value);
            //到达时间
            string LandTime = Convert.ToString(dataGridView1.SelectedRows[0].Cells[3].Value);
            //成人票价
            string Price = Convert.ToString(dataGridView1.SelectedRows[0].Cells[4].Value);
            //出发地
            string formCity = cmbGo.Text;
            //目的地
            string toidCity = cmbBourn.Text;
            //赋值给第二个分组框text文本框各个值
            txtNo.Text = Flightnum.ToString();
            textBox2.Text = Airways;
            txtTime.Text = LeaveTime;
            txtG.Text = LandTime;
            txtfares.Text = Price.ToString();
            textBox3.Text = formCity;
            txtDd.Text = toidCity;


        }






        /// <summary>
        /// 实现航班预定功能
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnreserve_Click(object sender, EventArgs e)
        {
            //创建对象的连接
            SqlConnection conn = new SqlConnection(DBHelper.str);
            //获取时间
            string date = dateTimePicker1.Value.ToString();
            //获取随机数
            Random dom = new Random();
            int num = dom.Next(10000, 10000000);
            try
            {
                //打开数据库
                conn.Open();

                //时间间隔的比较
                if (DateTime.Now > dateTimePicker1.Value)
                {
                    MessageBox.Show("请i选择正确的出发时间！");

                }
                else
                {

                    //拼接sql语句
                    string sql = "insert into OrderInfo ([OrderId],[FlightNo],[LeaveDate],[Number]) VALUES ('" + num + "','" + textBox2 + "','" + txtTime.Text + "','" + txtfares.Text + "')";

                    SqlCommand cmd = new SqlCommand(sql, conn);
                    int Ex = cmd.ExecuteNonQuery();


                    if (Ex > 0)
                    {
                        MessageBox.Show("预定成功！订单编号为：" + num);
                    }
                    else
                    {
                        MessageBox.Show("添加失败！");
                    }
                }
               
               
                

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);

            }
            finally
            {
                conn.Close();
            }
        }







错误的提示语：