The CData ADO.NET Provider for FreshBooks implements two ADO.NET interfaces you can use to retrieve data from FreshBooks: FreshBooksDataAdapter and FreshBooksDataReader objects. Whereas FreshBooksDataAdapter objects retrieve a single result set of all the data that matches a query, FreshBooksDataReader objects fetch data in subset increments as needed.

Using the FreshBooksDataReader

The FreshBooksDataReader retrieves data faster than the FreshBooksDataAdapter because it can retrieve data in pages. As you read data from the FreshBooksDataReader, it periodically requests the next page of results from the data source, if required. This causes results to be returned at a faster rate. The following example selects all the columns from the Clients table:

C#

string connectionString = "InitiateOAuth=GETANDREFRESH;OAuthClientId=MyClientId;OAuthClientSecret=MyClientSecret;CallbackURL=http://localhost:33333";

using (FreshBooksConnection connection = new FreshBooksConnection(connectionString)) {
  FreshBooksCommand cmd = new FreshBooksCommand("SELECT * FROM Clients", connection);
  
  FreshBooksDataReader rdr = cmd.ExecuteReader();

  while (rdr.Read()) {
    Console.WriteLine(String.Format("\t{0} --> \t\t{1}", rdr["Email"], rdr["Username"]));
  }
}

VB.NET

Dim connectionString As String = "InitiateOAuth=GETANDREFRESH;OAuthClientId=MyClientId;OAuthClientSecret=MyClientSecret;CallbackURL=http://localhost:33333"

Using connection As New FreshBooksConnection(connectionString)
  Dim cmd As New FreshBooksCommand("SELECT * FROM Clients", connection)

  Dim rdr As FreshBooksDataReader = cmd.ExecuteReader()

  While rdr.Read()
    Console.WriteLine([String].Format(vbTab & "{0} --> " & vbTab & vbTab & "{1}", rdr("Email"), rdr("Username")))
  End While
End Using