使用C＃将点符号插入到MySQL错误

Question

I'm facing a strange problem, I do an INSERT query to MySQL DB

                string site = txtSite.Text;
                string query = "INSERT INTO `site`(`id`, `url`, `status`) VALUES (NULL,?url, 1)";

                MySqlCommand cmd = new MySqlCommand(query);
                cmd.Parameters.AddWithValue("?url", site);
                //cmd.Parameters.AddWithValue("?url", "abc.com");
                cmd.Connection = (MySqlConnection)connection;
                cmd.Prepare();

                cmd.ExecuteNonQuery();

1. If I enter "abc.com" into textbox txtSite, and run the code, it said error

Fatal error encountered during command execution.

2. But if I don't get value of txtSite, I put "abc.com" to ?url directly, the cmd run OK, not error.

Can you have any ideas?

Answer 1

I believe this is a syntax issue. The following code may work for you.

string site = txtSite.Text;
string query = "INSERT INTO `site`(`id`, `url`, `status`) VALUES (NULL, @url, 1)";

MySqlClientconn conn = new MySqlConnection();
conn.Open();

MySqlCommand cmd = new MySqlCommand();
cmd.Connection = conn;
cmd.CommandText = query;
cmd.Prepare();

cmd.Parameters.AddWithValue("@url", site);

cmd.ExecuteNonQuery();

I am assuming you are using the MySQL Connector/Net library. Don't forget to close the connection and dispose of the command and the connection when you are done.

Reference

For more info on using the MySQL Connector/Net library, see the following: https://dev.mysql.com/doc/connector-net/en/connector-net-programming-prepared-preparing.html