怎么确定.net和mysql已经建立了连接

            MySqlConnection mysqlcon = new MySqlConnection();
            ////
            ////
            if (mysqlcon.State = ConnectionState.Open)
            {
                ////
            }

------解决方案--------------------
mysqlcon.State == ConnectionState.Open

……

------解决方案--------------------
try catch不到错误应该就OK了.
或者 送出一个Query,看看是否返回结果.