条件表达式中的数据类型不匹配。在c＃中

Question

/*connection ,command, and link between connection & command objects are done properly and they are working*/

cmd.CommandText = "Update student SET sname='"+snaame+"',fee='"+fees+"' where sno='"+snum+"'";
cmd.Parameters.Clear();
cmd.CommandType = CommandType.Text;
con.Open();
cmd.ExecuteReader();
con.Close();

Answer 1

检查数据库中fee和sno的数据类型，如果是varchar，那么请删除它周围的单引号

fee='"+fees+"' where sno='"+snum+"'"