不可调用成员 'DetailsForm.cmd' 不能像方法一样使用

Non-invocable member 'DetailsForm.cmd' cannot be used like a method

我正在尝试使命令正常工作,但它不起作用,请帮忙。此错误出现在 cmd("delete

我有 sqlcommand 命令;

private void DeleteRecordBtn_Click(object sender, EventArgs e)
    {
        cmd("delete blacklist1 where idnumber=@Idnumber", con);
        con.Open();
        cmd.Parameters.AddWithValue("@idnumber", UID.Text);
        cmd.ExecuteNonQuery();
        con.Close();

    }

这一行:

cmd("delete blacklist1 where idnumber=@Idnumber", con);

应该是:

cmd = new SqlCommand("delete blacklist1 where idnumber=@Idnumber", con);

但是,您应该将它放在 using 块中,以便在它完成后释放 cmd 资源。参见:SqlCommand with using statement