how run access query with params

i have this code for update datetime fileds in access using params

SQL = "update ConfTbl set D_from = @MyFrom , D_to = @MyTo where Code = " + Convert.ToInt32(TmpCode1) + "";
OleDbCommand Cmd = Conn.CreateCommand();
OleDbParameter dateparam1 = Cmd.Parameters.AddWithValue("@MyFrom", DbType.DateTime);
dateparam1.Value = dt_From.Value;
OleDbParameter dateparam2 = Cmd.Parameters.AddWithValue("@MyTo", DbType.DateTime);
dateparam2.Value = dt_To.Value;
Cmd.CommandText = SQL;
Cmd.ExecuteNonQuery();

how to change this for run query that find between two dates ?

somthing like: select * from ConfTbl where Tdate >= #MyFrom# and Tdate <= #MyTo#

i try this:

SQL = @"select * from ReturnConfTbl where Tdate >= @MyFrom and Tdate <= @MyTo";
        OleDbCommand Cmd = Conn.CreateCommand();
        OleDbParameter dateparam1 = Cmd.Parameters.AddWithValue("@MyFrom", DbType.DateTime);
        dateparam1.Value = dt_from_A.Value;
        OleDbParameter dateparam2 = Cmd.Parameters.AddWithValue("@MyTo", DbType.DateTime);
        dateparam2.Value = dt_to_A.Value;
        Cmd开发者_Go百科.CommandText = SQL;
        Cmd.ExecuteNonQuery();
        adp = new OleDbDataAdapter(SQL, Conn);
        adp.Fill(dsView, "ReturnConfTbl");
        adp.Dispose();
        this.dataGridView3.DataSource = dsView.Tables[0].DefaultView;

and got this error: Data type mismatch in criteria expression.

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You can use the BETWEEN keyword. e.g.

SELECT *
FROM ConfTbl
WHERE 
    Tdate BETWEEN #MyFrom# AND #MyTo#

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just have a look at the TSQL between statement.. http://msdn.microsoft.com/en-us/library/ms187922.aspx