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Custom Code Field

Updated on Jun 16, 2026

Fields in RadFlowDocument consist of a code fragment and a result fragment as explained in the Fields article. Some fields have a direct representation in the document model, for example, Hyperlinks. For all other fields, you can use the CustomCodeField class. You need some knowledge of how to correctly form the code of the field.

Field Syntax

Here is the basic syntax of a field code:

Syntax
field-type [field-argument] [switches]

field-type: The type of the field. For example: HYPERLINK.
argument: The argument of the field. This is optional because some of the fields do not require an argument.
switches: Additional properties of the field. More information on the topic is available in the Fields article.

Inserting

The suggested approach for inserting code fields is through RadFlowDocumentEditor. The InsertField() method accepts code as the first argument and the result as the second argument.

The following are some commonly used fields. The complete list of field codes and the switches for each of them is available in the Docx specification.

In all examples, the result fragment is also inserted. However, if you export the document to Docx format, you can use the AutoUpdateFields property. It forces all fields to be updated when the document is opened in MS Word or another editor.

Inserting PAGE Field

Example 1 shows how to insert a PAGE field representing the current page number in the document.

Example 1: Insert PAGE field

	editor.InsertField("PAGE  \\* ROMAN", "«VII»");

The \\* ROMAN is a general formatting switch that formats a numeric result using uppercase Roman numerals.

Inserting NUMPAGES Field

Example 2 demonstrates how a combination of PAGE and NUMPAGES fields can be inserted to show the current page and the total page count in the document.

Example 2: Insert NUMPAGES field

	editor.InsertText("Page ");
	editor.InsertField("PAGE", "3");
	editor.InsertText(" of ");
	editor.InsertField("NUMPAGES", "5");

Inserting AUTHOR Field

Example 3 demonstrates how to insert an AUTHOR field showing the name of the author of the document.

Example 3: Insert AUTHOR field

	editor.InsertField("AUTHOR  \\* Upper", "«JOHN DOE»");

The \\* Upper switch converts all letters in the result to uppercase.

Inserting Table of Contents Field

Example 4 shows how to insert a table of contents (TOC) field.

Example 4: Insert Table of Contents field

	FieldInfo tocField = editor.InsertField("TOC \\o \"1-3\" \\h \\z \\u", "«result»");
	tocField.IsDirty = true;

The following table describes the available switches for this field:

Switch	Description
\o "1-3"	Specifies that the first three heading levels are included in the table of contents
\h	Makes the table of contents entries hyperlinks
\z	Hides tab leader and page numbers in Web layout view
\u	Uses the applied paragraph outline level

The IsDirty property is set so that the TOC field is updated when the document is loaded inside an editor like Microsoft Word.