Question

你好我遇到了＃34的异常问题; ExecuteNonQuery需要一个开放且可用的连接。连接的当前状态已关闭。＆＃34;

public void AddCustomer(Customer customer)
    {
        string connectionString = @"Data Source=LIRON-PC\SQLEXPRESS;Initial Catalog=C:\Program Files\Microsoft SQL Server\MSSQL12.SQLEXPRESS\MSSQL\DATA\MatokMmagnet.mdf;Integrated Security=True";
        using (m_sqlConnection = new SqlConnection(connectionString))
        {
            m_cmd = new SqlCommand();
            m_cmd.CommandType = CommandType.Text;
            m_cmd.Connection = m_sqlConnection;

            m_cmd.Parameters.AddWithValue("@id", customer.id);
            m_cmd.Parameters.AddWithValue("@FirstName", customer.FirstName);
            m_cmd.Parameters.AddWithValue("@LastName", customer.LastName);
            m_cmd.Parameters.AddWithValue("@Password", customer.Password);
            m_cmd.CommandText = "INSERT INTO Customers (id, FirstName, LastName, Password)VALUES (@id, @FirstName, @LastName, @Password)";
            try
            {
                m_cmd.ExecuteNonQuery();
            }
            catch(Exception e)
            {
                Console.WriteLine( e.Message);
            }
            finally
            {
                m_sqlConnection.Close();
            }
        }
    }

Answer 1

与错误一样，您必须在执行查询之前打开连接，如下所示：

public void AddCustomer(Customer customer)
{
    string connectionString = @"Data Source=LIRON-PC\SQLEXPRESS;Initial Catalog=C:\Program Files\Microsoft SQL Server\MSSQL12.SQLEXPRESS\MSSQL\DATA\MatokMmagnet.mdf;Integrated Security=True";
    using (m_sqlConnection = new SqlConnection(connectionString))
    {`
        m_sqlConnection.open();
        //....
    }
}

c＃＆＃34; ExecuteNonQuery需要一个开放且可用的连接。连接的当前状态已关闭。＆＃34;

1 个答案: