Rapidly Develop USPS-Driven Apps with Active Query Builder

Leverage the Active Query Builder SQL interface builder and the ease of .NET data access to create data-driven WinForms and ASP.NET apps.

Write standard .NET to expose USPS data through an SQL interface: Active Query Builder helps developers write SQL interfaces; the CData ODBC Driver for USPS enables standards-based access to USPS. This integration uses the Microsoft ADO.NET Provider for ODBC as a bridge between the ODBC Driver and the Active Query Builder objects to build a visual SQL composer.

Connect to USPS as an ODBC Data Source

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.

To authenticate with USPS, set the following connection properties.

  • PostageProvider: The postage provider to use to process requests. Available options are ENDICIA and STAMPS. If unspecified, this property will default to ENDICIA.
  • UseSandbox: This controls whether live or test requests are sent to the production or sandbox servers. If set to true, the Password, AccountNumber, and StampsUserId properties are ignored.
  • StampsUserId: This value is used for logging into authentication to the Stamps servers. This value is not applicable for Endicia and is optional if UseSandbox is true.
  • Password: This value is used for logging into Endicia and Stamps servers. If the postage provider is Endicia, this will be the pass phrase associated with your postage account. It is optional if UseSandbox is true.
  • AccountNumber: The shipper's account number. It is optional if UseSandbox is true.
  • PrintLabelLocation: This property is required to use the GenerateLabels or GenerateReturnLabels stored procedures. This should be set to the folder location where generated labels should be stored.

The Cache Database

Many of the useful task available from USPS require a lot of data. To ensure this data is easy to input and recall later, utilize a cache database to make requests. Set the cache connection properties in order to use the cache:

  • CacheLocation: The path to the cache location, for which a connection will be configured with the default cache provider. For example, C:\users\username\documents\uspscache

As an alternative to CacheLocation, set the combination of CacheConnection and CacheProvider to configure a cache connection using a provider separate from the default.

Use SQL to Interact with USPS

Follow the steps below to create a WinForms visual query builder.

  1. In a new Windows Forms project, drag the QueryBuilder from the Toolbox onto the form.
  2. Add a reference to ActiveQueryBuilder.ODBCMetadataProvider.
  3. Add an OdbcConnection and set the connection string to the DSN that you created in the first section. OdbcConnection connection = new OdbcConnection(); connection.ConnectionString = "DSN=USPS"
  4. Initialize ODBCMetadataProvider and GeneralSyntaxProvider instances and set the Connection property of the ODBCMetadataProvider object to the OdbcConnection. GenericSyntaxProvider syntaxProvider = new GenericSyntaxProvider(); ODBCMetadataProvider metadataProvider = new ODBCMetadataProvider(); metadataProvider.Connection = connection;
  5. Set the corresponding MetadataProvider and SyntaxProvider properties of the QueryBuilder object. queryBuilder1.MetadataProvider = metadataProvider; queryBuilder1.SyntaxProvider = syntaxProvider;
  6. Call the InitiatelizeDatabaseSchemaTree method of the QueryBuilder class to retrieve USPS metadata and generate a tree view of USPS tables. queryBuilder1.InitializeDatabaseSchemaTree();
  7. After creating the QueryBuilder, connect it to a TextBox or, as we use, the ActiveQueryBuilder SQLTextEditor: Drag and drop an SQLTextEditor onto the designer.

  8. Add the following code to the Validating event for the SQLTextEditor: private void sqlTextEditor1_Validating(object sender, CancelEventArgs e) { try { // Update the query builder with manually edited query text: queryBuilder1.SQL = sqlTextEditor1.Text; } catch (SQLParsingException ex) { e.Cancel = true; // Set caret to error position sqlTextEditor1.SelectionStart = ex.ErrorPos.pos; // Report error MessageBox.Show(ex.Message, "Parsing error"); } }
  9. Add the following to the SQLUpdated event: private void queryBuilder1_SQLUpdated(object sender, EventArgs e) { sqlTextEditor1.Text = queryBuilder1.FormattedSQL; }
  10. You can now build queries visually: Double-click a table in the Columns Pane Area and an entity/relationship diagram is displayed in the Query Building Area. Columns that you select in the diagram are added to the query.