mysql - C# Query: 'System.InvalidOperationException' | Additional information: Connection must be valid and open

Question

connectionString = @"server=localhost;database=" + lbDatabase.SelectedItem.ToString() + ";userid=root;password=;";

        string query = "SELECT order_id FROM orders WHERE id = 1";

        MySqlConnection connect = new MySqlConnection(connectionString);

        MySqlCommand cmd = new MySqlCommand(query, connect);

        reader = cmd.ExecuteReader();

Hello,

I have this problem when I run the following code. I get this not so very specific error:

An unhandled exception of type 'System.InvalidOperationException' occurred in MySql.Data.dll

Additional information: Connection must be valid and open.

If anyone could help me out I would really appreciate it,

Thank you.

Answer 1

The syntax for MySql Connectionstring is as follows:

Server=myServerAddress;Database=myDataBase;Uid=myUsername;Pwd=myPassword;

Note that you are using 'userid' and 'password' instead of 'uid' and 'pwd'.