Because There is already an open DataReader associated with this Connection which must be closed first. That has opened the DataReader associated with this command

Baidu for a long time in order to solve the above problem, this problem arises because the connection mysql after I will query some data first, and then built a button click later, you can delete the specified data, find the method is as follows:


To amend the code to the
Conn=new MySqlConnection (" server="+ textBox1txt +";" +
"The port=" + textBox2txt + ";" +
"User=" + textBox4txt + ";" +
"Password=" + textBox5txt + ";" +
"The database=" + textBox3txt + ";" +
"MultipleActiveResultSets=True");

As a result of the error



Trouble bosses to give directions,,,

CodePudding user response:

Delete this: "MultipleActiveResultSets=True", the current driver does not support this parameter,