我正在尝试在C# Winforms中运行以下代码片段。这段代码在pgsql 2.2.6适配器上运行良好。为了使其与pgsql3.0.5适配器正常工作,应进行哪些更正?谢谢。
NpgsqlConnection conn = new NpgsqlConnection(MainForm2.MyConString);
{
conn.Open();
using (NpgsqlCommand cmd = new NpgsqlCommand("SELECT rfid,name,sc_id from passenger ORDER by name", conn))
{
NpgsqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
var obj = new PassengerClass
{
RFID = dr.GetString(0),
Name = dr.GetString(1),
sc_id = dr.GetInt32(2)
};
s = dr.GetString(0);
try { ret.Add(s, obj); }
catch (Exception ex) { SM.Debug("Fail to add RFID Name in hash RFID:" + s + ex.ToString()); }
}
}
MainForm2.PassHash = ret;
try
{
using (NpgsqlCommand cmd = new NpgsqlCommand(string.Format("UPDATE place set useridx ={0} where useridx=0", MainForm2.userIDX), conn))
cmd.ExecuteNonQuery();
using (NpgsqlCommand cmd = new NpgsqlCommand(string.Format("UPDATE zonename set useridx ={0} where useridx=0", MainForm2.userIDX), conn))
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
SM.Debug("Error on update users IDX for place and zone with value 0 :" + ex.ToString());
}
因此,在第二个命令语句中,它给出了以下错误:
类型为“System.InvalidOperationException”的第一次机会异常在 Npgsql.dll 中发生
附加信息:操作已经在进行中。