Related Ado.net For MySql

Question

Hi i have just shifted from ADODB to Ado.net for MySql. I am new to this system.

After going thru the forums i have defined the connection, adapter, reader , command. 

 

I defined in all this in a class, i am calling that class in every form so that i dont have to created the same for every form. I have written things like following

public MySqlConnection conn;
public MySqlCommand cmd;
public MySqlDataReader dr;
public MySqlDataAdapter da;

the DB is conneced through DSN. Here everything is working fine. But while working i got error message like

 

"There is already an open DataReader associated with this Command which must be closed"

 

So i searched on forum, but i being new to this things , i request you to please kindly suggest how i can close connect, open connected and how i should declear variables in a class. 

 

 I will be very thankful for this in advance. i am developing a customized software , so asap help is very much appriciated.

 

Thank you