If you are about to connect your WPF application's data to a template, the first question is what form that data has today: classes, ADO.NET tables, JSON or XML. MailMerge merges each of them, and one template serves them all as long as names and hierarchy match. Here you find which method merges which kind of data, how the Reporting tab receives the same data for template design and which page covers each kind.

How Data Reaches a Template

Two classes work with the data:

MailMerge merges it. A merge method takes the data and fills the template in a TextControl or ServerTextControl.
DataSourceManager describes it. The DataSourceManager of the WPF Reporting tab loads the same kinds of data, analyzes their tables, columns and relations and fills the drop-downs from which users insert fields and blocks.

Whatever the kind, the data becomes tables: the records you merge form the master table, whose columns fill merge fields, and nested collections or related tables fill merge blocks. Overview explains this model.

Data	Merge with	Load for design with	Page
A business object or a collection of them, dictionaries	MergeObject, MergeObjects	`LoadSingleObject`, `LoadObjects`, `LoadAssembly`	Objects and Collections
A `DataTable`, or a `DataSet` with relations	Merge	`LoadDataTable`, `LoadDataSet`	DataSets and DataTables
A JSON string	MergeJsonData	`LoadJson`	JSON and XML
An XML file or string	`Merge`, after `DataSet.ReadXml`	`LoadXmlFile`, `LoadXmlString`	JSON and XML

Data source configuration files, which store a database connection for the merge, are a Windows Forms feature; Data Source Configuration Files explains what WPF applications do instead.

Data Sources in the Reporting Tab

With Select Data Source, users of the WPF Reporting tab load an XML file, an assembly or a JSON file for template design; data from a database reaches the tab only through your code, because the WPF tab can't connect a database. Reporting Ribbon and WPF Dialog Boxes describes the commands, and each page of this section shows the DataSourceManager method that loads its kind of data.

Choose a Data Source

If your data is	Use
Classes or view models of your application, or data you query into objects	Business objects: Objects and Collections
Rows from a database in ADO.NET form	A `DataSet` with relations: DataSets and DataTables
The response of a web service, a file from another system	JSON or XML: JSON and XML

Business objects and JSON carry the hierarchy of the document without extra relations, which makes them the most direct choices for new applications.

Pages in This Section

Objects and Collections: merge business objects, dictionaries and anonymous objects, rename fields with attributes.
DataSets and DataTables: merge tables with relations and edit relations in the Reporting tab.
JSON and XML: merge JSON, handle invalid JSON, read XML into a DataSet and set parsing cultures.
Data Source Configuration Files: why configuration files are Windows Forms only, and the WPF alternative.