C#怎么取oracle系统时间?

C#如何取oracle系统时间????
我想这样取oracle的系统时间
string   myConnString   =   "user   id=newhis45;datasource=oraback;password=his ";
con   =   new   OracleConnection(myConnString);
comm   =   con.CreateCommand();
con.Open();
this.comm.CommandText   =   "select   sysdate   time   from   dual ";
reader   =   comm.ExecuteReader();
this.textBox1.Text   =   reader.GetOracleDateTime(0).ToString();

可是不行！请问如何做才正确？？？？？

[解决办法]
this.comm.CommandText = "select sysdate from dual ";