RESTORE DATABASE

Question

i did back up using the following code

public static void backups()

{

string str = "use point_of_sale";

string str1 = "Backup database point_of_sale to disk='E:\\backupfile.bak'WITH FORMAT, MEDIANAME = 'SQLServerBackups', NAME = 'Full Backup of pos'";

SqlCommand cmd1 = new SqlCommand(str, Connection.Getconnection());

SqlCommand cmd2 = new SqlCommand(str1, Connection.Getconnection());

cmd1.ExecuteNonQuery(); cmd2.ExecuteNonQuery();

}

 now i have a restore button .plz tell me the code i should enter