OracleDataReader Read(); return false and System.NullReferenceException
I have done this manny times but now I get a error and I don't know how to fix it. The variables aren't null, they have value; I tried this in the DB and all is ok it return 1 row
List<Partido_E> lista = new List<Partido_E>();
try
{
conexion = bd.LeerDeBaseDeDatos();
orden = new OracleCommand(
@"select * from partido
where TO_CHAR(fecha, 'DD/MM/YYYY') = :anyo AND
equipo_l = :equipol AND
equipo_v = :equipov ", conexion);
orden.Parameters.Add(new OracleParameter("anyo", fecha));
orden.Parameters.Add(new OracleParameter("equipol", equipoL));
orden.Parameters.Add(new OracleParameter("equipov", equipoV));
orden.BindByName = true;
lector = orden.ExecuteReader();
while(lector.Read())
{
lista.Add(new Partido_E(lector.GetString(0),
lector.GetString(1),
lector.GetDateTime(2),
lector.GetString(3),
lector.GetString(4),
lector.IsDBNull(5) ? 0 : lector.GetInt32(5),
lector.IsDBNull(6) ? 0 : lector.GetInt32(6),
lector.IsDBNull(7) ? 0 : lector.GetInt32(7)
));
}
lector.Close();
lector.Dispose();
orden.Dispose();
bd.CerrarConexion();
}
catch (Exception e)
{
Console.WriteLine("Error " + e.ToString());
Console.ReadLine();
}
return lista;
c# oracle oracle11g odp.net
edited Nov 20 at 4:32
T.S.
9,63593153
asked Nov 20 at 1:50
xLioneth
12
add a comment |
I have done this manny times but now I get a error and I don't know how to fix it. The variables aren't null, they have value; I tried this in the DB and all is ok it return 1 row
List<Partido_E> lista = new List<Partido_E>();
try
{
conexion = bd.LeerDeBaseDeDatos();
orden = new OracleCommand(
@"select * from partido
where TO_CHAR(fecha, 'DD/MM/YYYY') = :anyo AND
equipo_l = :equipol AND
equipo_v = :equipov ", conexion);
orden.Parameters.Add(new OracleParameter("anyo", fecha));
orden.Parameters.Add(new OracleParameter("equipol", equipoL));
orden.Parameters.Add(new OracleParameter("equipov", equipoV));
orden.BindByName = true;
lector = orden.ExecuteReader();
while(lector.Read())
{
lista.Add(new Partido_E(lector.GetString(0),
lector.GetString(1),
lector.GetDateTime(2),
lector.GetString(3),
lector.GetString(4),
lector.IsDBNull(5) ? 0 : lector.GetInt32(5),
lector.IsDBNull(6) ? 0 : lector.GetInt32(6),
lector.IsDBNull(7) ? 0 : lector.GetInt32(7)
));
}
lector.Close();
lector.Dispose();
orden.Dispose();
bd.CerrarConexion();
}
catch (Exception e)
{
Console.WriteLine("Error " + e.ToString());
Console.ReadLine();
}
return lista;
c# oracle oracle11g odp.net
edited Nov 20 at 4:32
T.S.
9,63593153
asked Nov 20 at 1:50
xLioneth
12
You should preferWHERE fecha = :anyoandorden.Parameters.Add(new OracleParameter("anyo", OracleDbType.Date)).Value = fecha.Date;(assumingfechais a DateTime value rather than a string)
– Wernfried Domscheit
Nov 20 at 7:20
The fecha is string, isn't DateTime
– xLioneth
Nov 20 at 11:30
add a comment |
I have done this manny times but now I get a error and I don't know how to fix it. The variables aren't null, they have value; I tried this in the DB and all is ok it return 1 row
List<Partido_E> lista = new List<Partido_E>();
try
{
conexion = bd.LeerDeBaseDeDatos();
orden = new OracleCommand(
@"select * from partido
where TO_CHAR(fecha, 'DD/MM/YYYY') = :anyo AND
equipo_l = :equipol AND
equipo_v = :equipov ", conexion);
orden.Parameters.Add(new OracleParameter("anyo", fecha));
orden.Parameters.Add(new OracleParameter("equipol", equipoL));
orden.Parameters.Add(new OracleParameter("equipov", equipoV));
orden.BindByName = true;
lector = orden.ExecuteReader();
while(lector.Read())
{
lista.Add(new Partido_E(lector.GetString(0),
lector.GetString(1),
lector.GetDateTime(2),
lector.GetString(3),
lector.GetString(4),
lector.IsDBNull(5) ? 0 : lector.GetInt32(5),
lector.IsDBNull(6) ? 0 : lector.GetInt32(6),
lector.IsDBNull(7) ? 0 : lector.GetInt32(7)
));
}
lector.Close();
lector.Dispose();
orden.Dispose();
bd.CerrarConexion();
}
catch (Exception e)
{
Console.WriteLine("Error " + e.ToString());
Console.ReadLine();
}
return lista;
c# oracle oracle11g odp.net
edited Nov 20 at 4:32
T.S.
9,63593153
asked Nov 20 at 1:50
xLioneth
12
I have done this manny times but now I get a error and I don't know how to fix it. The variables aren't null, they have value; I tried this in the DB and all is ok it return 1 row
List<Partido_E> lista = new List<Partido_E>();
try
{
conexion = bd.LeerDeBaseDeDatos();
orden = new OracleCommand(
@"select * from partido
where TO_CHAR(fecha, 'DD/MM/YYYY') = :anyo AND
equipo_l = :equipol AND
equipo_v = :equipov ", conexion);
orden.Parameters.Add(new OracleParameter("anyo", fecha));
orden.Parameters.Add(new OracleParameter("equipol", equipoL));
orden.Parameters.Add(new OracleParameter("equipov", equipoV));
orden.BindByName = true;
lector = orden.ExecuteReader();
while(lector.Read())
{
lista.Add(new Partido_E(lector.GetString(0),
lector.GetString(1),
lector.GetDateTime(2),
lector.GetString(3),
lector.GetString(4),
lector.IsDBNull(5) ? 0 : lector.GetInt32(5),
lector.IsDBNull(6) ? 0 : lector.GetInt32(6),
lector.IsDBNull(7) ? 0 : lector.GetInt32(7)
));
}
lector.Close();
lector.Dispose();
orden.Dispose();
bd.CerrarConexion();
}
catch (Exception e)
{
Console.WriteLine("Error " + e.ToString());
Console.ReadLine();
}
return lista;
c# oracle oracle11g odp.net
c# oracle oracle11g odp.net
edited Nov 20 at 4:32
T.S.
9,63593153
asked Nov 20 at 1:50
xLioneth
12
edited Nov 20 at 4:32
T.S.
9,63593153
asked Nov 20 at 1:50
xLioneth
12
edited Nov 20 at 4:32
T.S.
9,63593153
edited Nov 20 at 4:32
T.S.
9,63593153
edited Nov 20 at 4:32
T.S.
9,63593153
9,63593153
asked Nov 20 at 1:50
xLioneth
12
asked Nov 20 at 1:50
xLioneth
12
asked Nov 20 at 1:50
xLioneth
12
12
You should preferWHERE fecha = :anyoandorden.Parameters.Add(new OracleParameter("anyo", OracleDbType.Date)).Value = fecha.Date;(assumingfechais a DateTime value rather than a string)
– Wernfried Domscheit
Nov 20 at 7:20
The fecha is string, isn't DateTime
– xLioneth
Nov 20 at 11:30
add a comment |
You should preferWHERE fecha = :anyoandorden.Parameters.Add(new OracleParameter("anyo", OracleDbType.Date)).Value = fecha.Date;(assumingfechais a DateTime value rather than a string)
– Wernfried Domscheit
Nov 20 at 7:20
The fecha is string, isn't DateTime
– xLioneth
Nov 20 at 11:30
You should prefer
WHERE fecha = :anyo and orden.Parameters.Add(new OracleParameter("anyo", OracleDbType.Date)).Value = fecha.Date; (assuming fecha is a DateTime value rather than a string)– Wernfried Domscheit
Nov 20 at 7:20
You should prefer
WHERE fecha = :anyo and orden.Parameters.Add(new OracleParameter("anyo", OracleDbType.Date)).Value = fecha.Date; (assuming fecha is a DateTime value rather than a string)– Wernfried Domscheit
Nov 20 at 7:20
The fecha is string, isn't DateTime
– xLioneth
Nov 20 at 11:30
The fecha is string, isn't DateTime
– xLioneth
Nov 20 at 11:30
add a comment |
1 Answer
1
active
oldest
votes
Here is your problem - read comments
while (lector.Read())
{
// if you never come here, your reader is closed
}
lector.Close(); // <-- problem here
Oracle:
An OracleDataReader instance is constructed by a call to the ExecuteReader method of the OracleCommand object. The only properties that can be accessed after the DataReader is closed or has been disposed, are IsClosed and RecordsAffected.
This line lector.Read() can not throw null reference exception because line before that lector = orden.ExecuteReader(); will always return reader. If no rows, it will be closed.
Your code is not wormed well. should be
using (conn = new connection/getconnection)
{
using (cmd = new command)
{
using (reader = cmd.ExecuteReader)
{
} // no need to explicitly dispose/close here
}
}
answered Nov 20 at 4:26
T.S.
9,63593153
add a comment |
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1 Answer
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active
oldest
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1 Answer
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active
oldest
votes
active
oldest
votes
active
oldest
votes
Here is your problem - read comments
while (lector.Read())
{
// if you never come here, your reader is closed
}
lector.Close(); // <-- problem here
Oracle:
An OracleDataReader instance is constructed by a call to the ExecuteReader method of the OracleCommand object. The only properties that can be accessed after the DataReader is closed or has been disposed, are IsClosed and RecordsAffected.
This line lector.Read() can not throw null reference exception because line before that lector = orden.ExecuteReader(); will always return reader. If no rows, it will be closed.
Your code is not wormed well. should be
using (conn = new connection/getconnection)
{
using (cmd = new command)
{
using (reader = cmd.ExecuteReader)
{
} // no need to explicitly dispose/close here
}
}
answered Nov 20 at 4:26
T.S.
9,63593153
add a comment |
Here is your problem - read comments
while (lector.Read())
{
// if you never come here, your reader is closed
}
lector.Close(); // <-- problem here
Oracle:
An OracleDataReader instance is constructed by a call to the ExecuteReader method of the OracleCommand object. The only properties that can be accessed after the DataReader is closed or has been disposed, are IsClosed and RecordsAffected.
This line lector.Read() can not throw null reference exception because line before that lector = orden.ExecuteReader(); will always return reader. If no rows, it will be closed.
Your code is not wormed well. should be
using (conn = new connection/getconnection)
{
using (cmd = new command)
{
using (reader = cmd.ExecuteReader)
{
} // no need to explicitly dispose/close here
}
}
answered Nov 20 at 4:26
T.S.
9,63593153
add a comment |
Here is your problem - read comments
while (lector.Read())
{
// if you never come here, your reader is closed
}
lector.Close(); // <-- problem here
Oracle:
An OracleDataReader instance is constructed by a call to the ExecuteReader method of the OracleCommand object. The only properties that can be accessed after the DataReader is closed or has been disposed, are IsClosed and RecordsAffected.
This line lector.Read() can not throw null reference exception because line before that lector = orden.ExecuteReader(); will always return reader. If no rows, it will be closed.
Your code is not wormed well. should be
using (conn = new connection/getconnection)
{
using (cmd = new command)
{
using (reader = cmd.ExecuteReader)
{
} // no need to explicitly dispose/close here
}
}
answered Nov 20 at 4:26
T.S.
9,63593153
Here is your problem - read comments
while (lector.Read())
{
// if you never come here, your reader is closed
}
lector.Close(); // <-- problem here
Oracle:
An OracleDataReader instance is constructed by a call to the ExecuteReader method of the OracleCommand object. The only properties that can be accessed after the DataReader is closed or has been disposed, are IsClosed and RecordsAffected.
This line lector.Read() can not throw null reference exception because line before that lector = orden.ExecuteReader(); will always return reader. If no rows, it will be closed.
Your code is not wormed well. should be
using (conn = new connection/getconnection)
{
using (cmd = new command)
{
using (reader = cmd.ExecuteReader)
{
} // no need to explicitly dispose/close here
}
}
answered Nov 20 at 4:26
T.S.
9,63593153
answered Nov 20 at 4:26
T.S.
9,63593153
answered Nov 20 at 4:26
T.S.
9,63593153
answered Nov 20 at 4:26
T.S.
9,63593153
9,63593153
add a comment |
add a comment |
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You should prefer
WHERE fecha = :anyoandorden.Parameters.Add(new OracleParameter("anyo", OracleDbType.Date)).Value = fecha.Date;(assumingfechais a DateTime value rather than a string)– Wernfried Domscheit
Nov 20 at 7:20
The fecha is string, isn't DateTime
– xLioneth
Nov 20 at 11:30