Catch SqlException嘗試通過按鈕單擊事件向sql數據庫添加數據時拋出錯誤無效語法

Question

我正在開發一個學校項目的應用程序，但是在向sql數據庫添加數據時遇到了麻煩。 計划是用戶將單擊一個按鈕以“添加”數據，這將打開一個新表單，其中包含各種文本框以輸入數據。 當用戶滿意時，單擊“添加詳細信息”，然后將這些添加到sql數據庫中。 問題是嘗試捕獲不斷返回錯誤，我不知道為什么，可能是一個容易修復的新眼睛的人。 代碼如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace CarsULike
{
public partial class AddCust : Form
{
    public AddCust()
    {
        InitializeComponent();
    }

    private void AddCust_Load(object sender, EventArgs e)
    {

    }

    private void AddCustBtn_Click(object sender, EventArgs e)
    {
        if (FirstNameTxtBox.Text == "")
        {
            MessageBox.Show("Please enter a First Name");
        }
        else if (SurnameTxtBox.Text == "")
        {
            MessageBox.Show("Please enter a Surname");
        }
        else if (TitleTxtBox.Text == "")
        {
            MessageBox.Show("Please enter a Title");
        }
        else if (Address1TxtBox.Text == "")
        {
            MessageBox.Show("Please enter an address");
        }
        else if (TownCityTxtBox.Text == "")
        {
            MessageBox.Show("Please enter a Town/City");
        }
        else if (PostCodeTxtBox.Text == "")
        {
            MessageBox.Show("Please enter a Postcode");
        }
        else
        {
            //stores the values entered as variables
            string firstName = FirstNameTxtBox.Text;
            string surname = SurnameTxtBox.Text;
            string title = TitleTxtBox.Text;
            string address1 = Address1TxtBox.Text;
            string address2 = Address2TxtBox.Text;
            string townCity = TownCityTxtBox.Text;
            string postCode = PostCodeTxtBox.Text;
            string mobPhone = MobPhoneTxtBox.Text;
            string homePhone = HomePhoneTxtBox.Text;
        }

        //establishes a connection with the database
        SqlConnection connection = new SqlConnection(@"Data Source=Lee-PC\SQLEXPRESS; Initial Catalog=CarsULike_P116274;Integrated Security=True");
        SqlCommand cmd = new SqlCommand();
        //SqlDataReader datareader;
        string sql;

        try
        {
            // this query is for insertion into the Customer table
            sql = "INSERT INTO Customer (FirstName, Surname, Title, AddressLine1, AddressLine2, TownCity, PostCode, EmailAddress, MobilePhoneNo, HomePhoneNo)";
            sql += String.Format("VALUES, @FirstName, @Surname, @Title, @AddressLine1, @AddressLine2, @TownCity, @PostCode, @EmailAddress, @MobilePhoneNo, @HomePhoneNo)");

            cmd = new SqlCommand(sql, connection);
            cmd.CommandText = sql;
            cmd.CommandType = CommandType.Text;

            cmd.Parameters.AddWithValue("@FirstName", FirstNameTxtBox.Text);
            cmd.Parameters.AddWithValue("@Surname", SurnameTxtBox.Text);
            cmd.Parameters.AddWithValue("@Title", TitleTxtBox.Text);
            cmd.Parameters.AddWithValue("@AddressLine1", Address1TxtBox.Text);
            cmd.Parameters.AddWithValue("@AddressLine2", Address2TxtBox.Text);
            cmd.Parameters.AddWithValue("@TownCity", TownCityTxtBox.Text);
            cmd.Parameters.AddWithValue("@PostCode", PostCodeTxtBox.Text);
            cmd.Parameters.AddWithValue("@EmailAddress", MobPhoneTxtBox.Text);
            cmd.Parameters.AddWithValue("@MobilePhoneNo", HomePhoneTxtBox.Text);
            cmd.Parameters.AddWithValue("@HomePhoneNo", HomePhoneTxtBox.Text);

            connection.Open(); //opens connection
            cmd.ExecuteNonQuery(); //writes to the database
            MessageBox.Show("Details Added", "Successful");
        }

        catch (SqlException ex)
        {
            throw new Exception("Error adding details", ex);

        }
        finally
        {
            connection.Close(); // Close connection
        }
    }

    private void CancelAddCustBtn_Click(object sender, EventArgs e)
    {
        this.Close();   // Close current form
    }
}

我已經環顧四周但似乎無法找到我正在尋找的東西..或者我只是不知道我在尋找什么！

Answer 1

更改

"VALUES, @FirstName, @Surname, @Title, @AddressLine1, @AddressLine2, @TownCity, @PostCode, @EmailAddress, @MobilePhoneNo, @HomePhoneNo)"

至

"VALUES ( @FirstName, @Surname, @Title, @AddressLine1, @AddressLine2, @TownCity, @PostCode, @EmailAddress, @MobilePhoneNo, @HomePhoneNo)"

將逗號更改為open-paren。

可能還有其他錯誤，但這肯定是一個錯誤。

此外，您可能希望調整catch語句以確保您看到確切的sql錯誤。 通常，SQL異常（或內部異常）將為您提供有關SQL代碼錯誤或連接問題是否存在問題的非常好的線索。

Answer 2

在這一部分

"VALUES, @FirstName

您未能打開稍后關閉的括號，這就是錯誤。