Question

我正在尝试创建一个简单的应用程序表单，用户可以输入'reservationid', 'bookid', 'EmployeeID' and 'reservedate'之类的数据。它来自我的程序库系统。 'reservationid' is an auto increment primary key，其余为BigInt50, NVarChar50 and DateTime10。所以我遇到了这个错误：Input String was not in a correct format。 It worked fine a while ago until I modified the 'reservationid' to auto increment所以我哪里出错了？我附上了我的代码示例。

任何帮助将不胜感激！提前谢谢！

namespace LibraryManagementSystemC4.User
{
    public partial class Reserving : System.Web.UI.Page
    {
        public string GetConnectionString()
        {
            return System.Configuration.ConfigurationManager.ConnectionStrings["LibrarySystemConnectionString"].ConnectionString;
        }
        //string reservationid
        private void ExecuteInsert(string bookid, string EmployeeID, string reservedate)
        {
            SqlConnection conn = new SqlConnection(GetConnectionString());

            string sql = "INSERT INTO BookReservation (reservationid, bookid, EmployeeID, reservedate) VALUES " + " (@reservationid, @bookid, @EmployeeID, @reservedate)";
            try
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand(sql, conn);
                SqlParameter[] param = new SqlParameter[3];

                //param[0] = new SqlParameter("@reeservationid", SqlDbType.Int, 50);
                param[0] = new SqlParameter("@bookid", SqlDbType.BigInt, 50);
                param[1] = new SqlParameter("@EmployeeID", SqlDbType.NVarChar, 50);
                param[2] = new SqlParameter("@reservedate", SqlDbType.DateTime, 10);

                //param[0].Value = reservationid;
                param[0].Value = bookid;
                param[1].Value = EmployeeID;
                param[2].Value = reservedate;

                for (int i = 0; i < param.Length; i++)
                {
                    cmd.Parameters.Add(param[i]);
                }

                cmd.CommandType = CommandType.Text;
                cmd.ExecuteNonQuery();
            }

            catch (System.Data.SqlClient.SqlException ex)
            {
                string msg = "Insert error";
                msg += ex.Message;
                throw new Exception(msg);
            }

            finally
            {
                conn.Close();
            }
        }

        protected void Page_Load(object sender, EventArgs e)
        {
            if (reservationidTextBox != null)
            {
                //reservationidTextBox.Text
                ExecuteInsert(bookidTextBox.Text, EmployeeIDTextBox.Text, reservationidTextBox.Text);

                ClearControls(Page);
            }

            else
            {
                Response.Write("Please input ISBN");
                bookidTextBox.Focus();
            }

            {
                //get bookid from Book Details and Employee PIN from current logged-in user
                bookidTextBox.Text = DetailsView1.SelectedValue.ToString();
                EmployeeIDTextBox.Text = HttpContext.Current.User.Identity.ToString();
            }
        }

        public static void ClearControls(Control Parent)
        {
            if (Parent is TextBox)
            {
                (Parent as TextBox).Text = string.Empty;
            }

            else
            {
                foreach (Control c in Parent.Controls)
                    ClearControls(c);
            }
        }
    }
}

Answer 1

如果reservationid自动递增，则将其从插入查询中删除

string sql = "INSERT INTO BookReservation ( bookid, EmployeeID, reservedate) VALUES (@bookid, @EmployeeID, @reservedate)";

也试试

            param[0].Value = Convert.ToInt64(bookid);
            param[1].Value = EmployeeID;
            param[2].Value = Convert.ToDate(reservedate);

Answer 2

在你对autoincrement进行预约后，你就不必这样做了

string sql = "INSERT INTO BookReservation (reservationid, bookid, EmployeeID, reservedate) VALUES " + " (@reservationid, @bookid, @EmployeeID, @reservedate)";

删除要插入的reservedid。喜欢

string sql = "INSERT INTO BookReservation ( bookid, EmployeeID, reservedate) VALUES (@bookid, @EmployeeID, @reservedate)";

Answer 3

这是因为当reservationid不是command parameters时，您没有将Auto Increment整数值传递给string reservationid。

我可以从您的代码中看到，您已声明{{1}}，但您没有为其分配任何值，其次它应该是整数值。

Answer 4

我知道这是非常严重的，但是由于Loupi对9Jun11的评论似乎他仍然有问题，我发布了实际答案。 Bala的回答是仍然给他输入类型不正确的格式错误;在值赋值中使用Convert.ToInt64语句将其绊倒。在分配参数值之前进行变量转换，它就是一个魅力。最可能的罪魁祸首是bookid是某种非零的空字符串表示（空白引号，空格，null，等等）。

编辑：快速简便的单行测试相对防范：

long numAccountNum = Int64.TryParse(AccountNum, out numAccountNum) ? Convert.ToInt64(AccountNum) : 0;

输入字符串的格式不正确

4 个答案: