After the first tutorials, a WPF application usually needs more than loading and saving: tables filled from data, headers with page numbers, fields, forms, tracked changes, printing and conversions that run while the window stays responsive. Each of these tasks is shown below in the code-behind of a window, together with the object model behind it, one page per element your application works with.

How Document Processing Works

A document lives either in the WPF TextControl that the user sees or in a ServerTextControl that has no user interface:

	`TXTextControl.WPF.TextControl`	`TXTextControl.ServerTextControl`
Declared	In XAML, as `WPF:TextControl`	In code, with `new`, `Create` and `using`
Shows the document	Yes	No
Thread	The UI thread of the window	Any thread, one instance per thread
Used for	The document the user edits	Documents your code builds, converts, merges or prints

Both share the classes that describe the content, such as Selection, Paragraph, Table, Section and TextField, so the same code builds a document in either. The examples of this section are handlers in MainWindow.xaml.cs for a TextControl named textControl1. Two rules hold throughout:

A collection belongs to the text part with the input focus. Tables, TextFields, Comments and similar collections of the TextControl contain the elements of the main text, a text frame or a header or footer, depending on where the cursor is. TextParts contains all parts.
Positions count from 0 or from 1. Selections and the input position start at 0; the Start of paragraphs, fields and other elements starts at 1.

Document Object Model describes both rules and the structure of a document.

Find the Right Page

Task	Page
Learn how the parts of a document are organized	Document Object Model
Start a document, set its page format, combine documents	Creating Documents
Load files, byte arrays, strings and streams	Loading Documents
Save, convert to PDF and control the output	Saving and Converting Documents
Find, replace and format text; styles and lists	Text, Paragraphs, and Stylesheets
Build tables and formulas	Tables and Calculations
Add images, text frames and shapes	Images, Text Frames, and Shapes
Add charts and barcodes	Charts and Barcodes
Set up sections, headers, footers and page numbers	Sections, Pages, Headers, and Footers
Work with fields, links, bookmarks and subtext parts	Fields and Subtext Parts
Create forms and validate their values	Forms and Conditional Instructions
Record, review and remove comments and changes	Comments and Tracked Changes
Edit XML data with a DTD and CSS	XML Processing
Print from code and in the background	Printing
Keep the window responsive during long work	Using ServerTextControl in Desktop Applications
Catch errors and exceptions	Exceptions and Error Handling
Validate form values with rules: operators, instruction types, radio button groups	Conditional Instructions
Read Word form fields and create content controls with field adapters	Content Controls

Recommended Order

Work through Document Processing in Getting Started, if you haven't yet.
Read Document Object Model: the other pages rely on it.
Continue with Loading Documents and Saving and Converting Documents.
When documents are processed outside the editor, read Using ServerTextControl in Desktop Applications, and before shipping, Exceptions and Error Handling.

The same elements from the user's side, with the ribbon and dialog boxes, are covered in Document Editor. Templates filled with data are the subject of Mail Merge and Reporting, and PDF-specific options of PDF Processing.

Pages in This Section

Document Object Model — text parts, collections, positions and units.
Creating Documents — new documents, page format and combined documents.
Loading Documents — load, append and insert, and LoadSettings.
Saving and Converting Documents — formats, partial saving and SaveSettings.
Text, Paragraphs, and Stylesheets — text, formatting, styles and lists.
Tables and Calculations — tables, cells and formulas.
Images, Text Frames, and Shapes — frames and their positions.
Charts and Barcodes — charts and barcodes in documents.
Sections, Pages, Headers, and Footers — page layout and page numbers.
Fields and Subtext Parts — marked text, links and ranges.
Forms and Conditional Instructions — fillable forms and their rules.
Comments and Tracked Changes — review markup.
XML Processing — XML files with DTD and CSS.
Printing — Print overloads, PrintDocument and the formatting printer.
Using ServerTextControl in Desktop Applications — background work and threads.
Exceptions and Error Handling — TX Text Control exceptions and where to catch them.
Conditional Instructions — rules that validate and change form fields.
Content Controls — content controls and legacy Word form fields through field adapters.