In this article I will share the code of a Windows-based application that helps to upload files into a Windows CE device as a .sdf file. First I will create the sdf file in the Application startup (Application bin folder) then transfer this sdf into a device using something.

Are you confused about .sdf files?

SQL Server saves a database in a .mdf file, correpondingly a Windows CE device saves a database in a .sdf file. But a .sdf database has some limitations. I will explain the limitations later.

We use a SqlCeEngine class to create a database.

Code to create a database

  1. public static void CreateDataBase()
  2. {
  3. public static string _DBPATH = Application.StartupPath;
  4. public static string _DBNAME = "Data.sdf";
  6. SqlCeEngine SqlEngine;
  7. strDBURL = _DBPATH + "\\" + _DBNAME;
  9. SqlEngine = new SqlCeEngine("data source=" + strDBURL + ";Max Buffer Size = 512; Max Database Size = 500");
  10. SqlEngine.CreateDatabase();
  12. }
  13. catch (Exception ex)
  14. {
  15. throw ex;
  16. }

I can set the maximum buffer size and maximum database size in the sdf file.

Code to create Table in Data.Sdf

  1. public static void CreateTable()
  2. {
  3. strConStr = "data source=" + strDBURL + ";Max Buffer Size = 512; Max Database Size = 500";
  4. SqlCeConnection cn = new SqlCeConnection();
  5. cn.ConnectionString = strConStr;
  6. cn.Open();
  7. SqlCeCommand objSqlCommand = new SqlCeCommand();
  8. objSqlCommand.Connection = cn;
  9. objSqlCommand.CommandType = CommandType.Text;
  10. try
  11. {
  12. strSQL = "CREATE TABLE FileData(";
  13. strSQL = strSQL + "UniqueID nvarchar(200),";
  14. strSQL = strSQL + "Serialnumber nvarchar(300) NULL,";
  15. strSQL = strSQL + "Customer nvarchar(500) NULL, ";
  16. strSQL = strSQL + "Rack nvarchar(500) NULL, ";
  17. strSQL = strSQL + "HHTId nvarchar(100) NULL, ";
  18. strSQL = strSQL + "BoxId nvarchar(300) NULL, ";
  19. strSQL = strSQL + "ScanDateTime nvarchar(200) NULL) ";
  20. objSqlCommand.CommandText = strSQL;
  21. objSqlCommand.ExecuteNonQuery();
  22. }
  23. catch (SqlCeException ex)
  24. {
  25. throw ex;
  26. }
  27. finally
  28. {
  29. cn.Close();
  30. cn = null;
  31. }
  32. }

Now my database Data.sdf is ready with the table named FileData.

Then I need to write code to transfer the sdf file to the device. Before that I need to check whether or not the device is connected. With the RAPI class it is very easy . It has some builtin Boolean methods that are eiter true or false, like:

OpenNETCF.Desktop.Communication.RAPI op = new OpenNETCF.Desktop.Communication.RAPI();

Don't confuse DevicePresent with Connect.

Note: the RAPI dll works if Microsoft Activesync is present in your system.

Conclusion

I have explained ever step that helps to create a sdf file database at the device end and the use of the RAPI dll to transfer sdf from a device to a Windows application and vice versa.

I will explain how to do DML operations in a sdf file from a windowsCE device application in my next article. Stay tuned.

Happy coding.