MySqlDataReader dataReader = cmd.ExecuteReader（）弹出窗口Form而不进入while循环

My connection is working fine. However, when it runs to MysqlDataREader dataReader line, it displays the Window Form and does not access the while loop to get my data. I am using dataGridView to display the info from my database. What did I do wrong? thanksMy connection is working fine. However, when it