Question

我正在尝试将用户添加到两个不同的表，从SQL Server Management Studio Express运行，仅为一个会话添加详细信息，请人们帮助解答如何将此数据用于最后会话结束后的数据库（我为糟糕的代码道歉，我目前只是一名学徒软件工程师）

namespace AddingANewUser
{
public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void AddNewUser(String employeeID, String firstName, String lastName, String username, String password, String managerID, String accessLevelID, String phoneNumber, String departmentID)
    {
        using (var connection = new SqlConnection(Properties.Settings.Default.CitySecretHRSystemConnectionString))
        {
            connection.Open();

            using (var updateEmployees = connection.CreateCommand())
            {
                updateEmployees.CommandText = "INSERT INTO Employees (EmployeeID, FirstName, LastName, PhoneNumber, AccessLevelID, ManagerID, DepartmentID) VALUES (@employeeID, @firstName, @lastName, @phoneNumber, @ accessLevelID, @managerID, @departmentID)";

                updateEmployees.Parameters.AddWithValue("@firstName", firstName);
                updateEmployees.Parameters.AddWithValue("@lastName", lastName);
                updateEmployees.Parameters.AddWithValue("@employeeID", employeeID);
                updateEmployees.Parameters.AddWithValue("@phoneNumber", phoneNumber);
                updateEmployees.Parameters.AddWithValue("@accessLevelID",   accessLevelID);
                updateEmployees.Parameters.AddWithValue("@managerID", managerID);
                updateEmployees.Parameters.AddWithValue("@departmentID", departmentID);
            }

            using (var updateLogIn = connection.CreateCommand())
            {
                updateLogIn.CommandText = "INSERT INTO LogInDetails (EmployeeID, Username, KeyWord) VALUES (@employeeID, @username, @keyWord)";

                updateLogIn.Parameters.AddWithValue("@employeeID", employeeID);
                updateLogIn.Parameters.AddWithValue("@username", username);
                updateLogIn.Parameters.AddWithValue("@keyWord", password);
            }
        }
    }

    private void btnSubmit_Click(object sender, EventArgs e)
    {
        try
        {
            AddNewUser(tbEmployeeID.Text, tbFirstName.Text, tbLastName.Text, tbUsername.Text, tbPassword.Text, tbManagerID.Text, tbAccessLevel.Text, tbPhoneNumber.Text, tbDeptID.Text);
        }
        catch (Exception err)
        {
            MessageBox.Show(err.Message);
        }
    }
}

Answer 1

我猜你错过了execute命令：

using (var updateEmployees = connection.CreateCommand())
{
    //...
    //... 
    updateEmployees.ExecuteNonQuery();
    //...
}

正如其他人正确指出的那样：

using语句以正确的方式调用对象上的Dispose方法，并且（如前所示使用它时）一旦调用Dispose，它也会导致对象本身超出范围。

简单来说，不需要调用connection.Close()作为using来处理它并在完成后关闭连接。

Answer 2

你必须使用下面提到的代码

 using (var connection = new SqlConnection(Properties.Settings.Default.CitySecretHRSystemConnectionString))
    {
        if (connection.State == ConnectionState.Closed)
            connection.Open();

        using (var updateEmployees = connection.CreateCommand())
        {
            updateEmployees.CommandText = "INSERT INTO Employees (EmployeeID, FirstName, LastName, PhoneNumber, AccessLevelID, ManagerID, DepartmentID) VALUES (@employeeID, @firstName, @lastName, @phoneNumber, @ accessLevelID, @managerID, @departmentID)";

            updateEmployees.Parameters.AddWithValue("@firstName", firstName);
            updateEmployees.Parameters.AddWithValue("@lastName", lastName);
            updateEmployees.Parameters.AddWithValue("@employeeID", employeeID);
            updateEmployees.Parameters.AddWithValue("@phoneNumber", phoneNumber);
            updateEmployees.Parameters.AddWithValue("@accessLevel", accessLevel);
            updateEmployees.Parameters.AddWithValue("@managerID", managerID);
            updateEmployees.Parameters.AddWithValue("@departmentID", departmentID);
            updateEmployees.ExecuteNonQuery();
        }


        using (var updateLogIn = connection.CreateCommand())
        {
            updateLogIn.CommandText = "INSERT INTO LogInDetails (EmployeeID, Username, KeyWord) VALUES (@employeeID, @username, @keyWord)";

            updateLogIn.Parameters.AddWithValue("@employeeID", employeeID);
            updateLogIn.Parameters.AddWithValue("@username", username);
            updateLogIn.Parameters.AddWithValue("@keyWord", password);
            updateLogIn.ExecuteNonQuery();
        }
    }

您已经实施了using阻止，因此无需关闭连接

Answer 3

您已撰写@phoneNumber, @ accessLevelID, @managerID,：@和accessLevel之间没有空格。此外，一旦您拨打accessLevel和其他时间accessLevelID，我认为accessLevel没有ID ......

在C＃中将值插入表中

3 个答案: