Error : "Fill: SelectCommand.Connection property has not been initialized."
Change the line
MySqlCommand cmd = new MySqlCommand("SELECT tes FROM ins");To
MySqlCommand cmd = new MySqlCommand("SELECT tes FROM ins", conn);And it should work.
Alternatively assign conn to the cmd.Connection property.
The problem with your code is that you never assign a connection to the command, hence the error saying that the connection is not initialized.
Try This
MySqlCommand cmd = new MySqlCommand("SELECT tes FROM ins",conn);or
MySqlCommand cmd = new MySqlCommand("SELECT tes FROM ins");cmd.Connection=conn;
I got also this problem. after search the problem found that the object of connection that i have provide SqlDataAdapter is not Initialize so the connection passed as null