How to bind a Snap document to multiple data sources in code

This example illustrates how you can bind a Snap document to multiple data sources:
- XPCollections with one-to-many relationship, 
- a data table contained in the System.Data.DataSet object,
- Excel data source,
and set one of the available data sources as the mail merge source ("Use for Mail Merge" option) using the SnapControl.Options.SnapMailMergeVisualOptions.DataSourceName property.