SDF文件是SQLCE数据库-您可以使用SqlCEConnector，SqlCECommand和类似的类在C#中访问它们:

SDF files are SQLCE databases - you can access them in C# using the SqlCEConnector, SqlCECommand and such like classes:

using (SqlCEConnection con = new SqlCEConnection(strConnect))
    {
    con.Open();
    using (SqlCECommand com = new SqlCECommand("SELECT iD, description FROM PurchaseTypes", con))
        {
        using (SqlCEDataReader reader = com.ExecuteReader())
            {
            while (reader.Read())
                {
                int id = (int) reader["iD"];
                string desc = (string) reader["description"];
                Console.WriteLine("ID: {0}\n    {1}", iD, desc);
                }
            }
        }
    }