OleDbDataReader problem in WinForm

 public OleDbDataReader ExecuteQueryReturnReader (string sql, string connStr) 

{
OleDbConnection conn = new OleDbConnection ();
OleDbDataReader reader = null;
try 

{
conn = new OleDbConnection (connStr);
conn.Open ();


OleDbCommand command = conn.CreateCommand ();
command.CommandText = sql;
reader = command.ExecuteReader ();
} 

catch 

{
} 

finally 

{
if (conn! = null) 

conn.Close ();
} 

return reader;
}

These are the following code in the project was so used:

 

string DataBase = "HCConfig.mdb";
string strConnection = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source ="
+ Application.StartupPath + "/ /" + DataBase;
ExecSql con = new ExecSql ();
string Sql = "select * form config where ID = 'sss'" ;
OleDbDataReader p = con.ExecuteQueryReturnReader (strConnection, Sql);
MessageBox.Show (p.FieldCount.ToString ());

But why is there the following error?
Additional information: Object reference not set to an instance of an object.
each execution to MessageBox.Show (p.FieldCount.ToString ()); always appear when this sentence! ! ! !
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OleDbDataReader p = con.ExecuteQueryReturnReader (Sql, strConnection) ;/ / not pass backwards?

------ Solution ------------------------------------ --------
finally
{
if (conn! = null)
conn.Close ();
}
connection has been closed before returning.

do not have to write this, there are already mature sqlhelper or oledbhelper.
------ Solution ----------------------- ---------------------
Well, just look at your reply to an SQL statement, I am very sure that your instance of OleDbDataReader P is a null your SQL statement error: select * form config where ID = 'sss' in the form wrong! Is from!!! Cause P is null, then you get back its property values ​​is certainly not the object reference to an instance of!
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own Kuangding Yeah, do not sink
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I wrote backwards, but still the error
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removed if (conn! = ; null)
conn.Close (); Nor I tried
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trace debug what chant, watching what is going wrong.
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Upstairs 2 is to say if you modify the error still being given good, then I can think of is your database query problem! Are you sure you execute SQL returns an instance of OleDbDataReader P is not null?
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Results posted to the sub, the word is misspelled! ! ! ! ! ! !