Question

I am using:

        if (connection.State != ConnectionState.Open)
        {
            OpenConnection();
        }

and

private bool OpenConnection()
{
    try
    {
        connection.Open();
        return true;
    }
    catch (MySqlException ex)
    {
        //When handling errors, you can your application's response based 
        //on the error number.
        //The two most common error numbers when connecting are as follows:
        //0: Cannot connect to server.
        //1045: Invalid user name and/or password.
        switch (ex.Number)
        {
            case 0:
                Console.WriteLine("Cannot connect to server.  Contact administrator");
                Console.Read();
                break;

            case 1045:
                Console.WriteLine("Invalid username/password, please try again");
                Console.Read();
                break;
        }
        return false;
    }
}

I always get System.InvalidOperationException: The connection is already open. it doesn’t make sense because I check if it’s open already.

Thanks in advance.

Answer 1

There are connection states other than open and closed: Broken, Closed, Connecting, Executing, Fetching. You should only try to open if it’s “Closed”. If anything else it needs to be handled differently.