Rtf syntax



Download 154.15 Kb.
Page1/6
Date conversion29.04.2016
Size154.15 Kb.
  1   2   3   4   5   6
Rich Text Format

RTF Syntax

The Rich Text Format (RTF) standard is a method of encoding formatted text and graphics for easy transfer between applications. Currently, users depend on special translation software to move word processing documents between different DOS applications, and between DOS applications and Apple Macintosh applications.


The RTF standard provides a standard format for text and graphics interchange that can be used with different output devices, operating environments, and operating systems. RTF uses the ANSI, Macintosh, or IBM PC character set to control the representation and formatting of a document, both on the screen and in print. With the RTF standard, documents composed under different operating systems and with different software applications can be transferred between those operating systems and applications.
An RTF file consists of unformatted text, "control words," "control symbols," and "groups." A standard RTF file consists of only 7-bit ASCII characters for ease of transport.
A "control word" is a specially formatted command that RTF uses to mark printer control codes and information that applications use to manage documents. A control word consists of a backslash followed by an alphabetic string and a delimiter, as shown in the following example
\rtf1É
A B C
A Backslash begins each control word

C Alphabetic string



C Numeric delimiter
The delimiter can be a space or one or more nonalphabetic characters. If a numeric parameter immediately follows the control word, this parameter is the delimiter, and is itself followed by a delimiter, also consisting of a space or one or more nonalphabetic characters.
A "control symbol" consists of a backslash followed by a single, nonalphabetic character. For example, \~ represents a nonbreaking space. Control symbols take no delimiters.
A "group" consists of text and control words or control symbols enclosed in braces ({}). Formatting specified within a group affects only the text within the group. Generally, text within a group inherits any formatting of the text preceding the group. However, Microsoft implementations of RTF assume that the footnote, header/footer, and annotation groups (described later in this document) do not inherit formatting of the preceding text. Therefore, to ensure that these groups will always be formatted correctly, you should set the formatting within these groups to the default with the \sectd, \pard, and \plain control words, and then add any desired formatting.
Any other characters in the file are plain text. As mentioned above, the backslash (\) and braces ({}) have special meaning in RTF. To use these characters as text, precede them with a backslash.
Software that takes a formatted file and turns it into an RTF file is called a "writer." Software that translates an RTF file into a formatted file is called a "reader." An RTF writer separates the application's control information from the plain text and writes a new file containing the plain text and the RTF groups associated with that text. An RTF reader does the converse of this procedure.
An entire RTF file is considered a group and must be enclosed in braces. The control word \rtfn must follow the first open brace. The numeric parameter identifies the version of the RTF standard used. The RTF standard described in this document corresponds to version 1.
The order of groups within an RTF file is important. Each group specifies the part of the document affected by the group and the different attributes of that text. An RTF file must begin with the following two control words in the following order
¥ RTF version (\rtfn)
¥ Character set
The RTF file can also include groups for fonts, styles, screen color, pictures, footnotes, annotations, headers and footers, summary information, fields, and bookmarks, as well as document, section, paragraph, and character formatting properties. If the font, style, screen color, and summary information groups and document formatting properties are included, they must precede the first plain text character in the document. If included, the group for fonts should precede the group for styles.
The groups are discussed in the following sections. If a group isn't used, it can be omitted.
Certain groups, referred to as "destinations," mark the beginning of a collection of related text. An example of this is the \footnote group, where the footnote text follows the control word. Destinations added after the RTF specification published in the March 1987 Microsoft Systems Journal may be preceded by the control symbol \*. This control symbol identifies destinations whose related text should be ignored if the RTF reader does not recognize the destination. RTF writers should follow this convention when adding new control words. Destinations whose related text should be inserted into the document even if the destination is not recognized should not use \*. In this document, all destinations that use \* will be shown with \* as part of the control word.

The Character Set

After specifying the RTF writer you must declare the character set. The RTF specification currently supports the following character sets




Control word

Character set

\ansi

ANSI (default)

\mac

Apple Macintosh

\pc

IBM PC

\pca

IBM PC page 850, used by IBM Personal System/2



The Font Table

This group contains descriptions of fonts and begins with the control word \fonttbl. All fonts available to the RTF writer can be included in the font table, even if the document doesn't use all the fonts.


A font is defined by its name, a font number, and a font family, as shown in the following example. Semicolons are used as delimiters between fonts.
{\fonttbl\f0\froman Tms Rmn;}É

A B C D
A Control word

B Font number

C Font family

D Font name
The font numbers represent the full font definitions in the group, and vary with each document. The font families are listed below


Control word

Font family

\fnil

Unknown or default fonts (default)

\froman

Roman, proportionally spaced serif fonts (TmsRmn, Palatino, etc.)

\fswiss

Swiss, proportionally spaced sans serif fonts (Swiss, etc.)

\fmodern

Fixed-pitch serif and sans serif fonts (Courier, Elite, Pica, etc.)

\fscript

Script fonts (Cursive, etc.)

\fdecor

Decorative fonts (Old English Zapf Chancery, etc.)

\ftech

Technical, symbol, and mathematical fonts (Symbol, etc.)

If an RTF file uses a default font, the default font number is specified with the \deffn control word which must precede the font table group. The RTF writer supplies the default font number used in the creation of the document as the numeric argument. The RTF reader then translates this number through the font table into the most similar font available on the reader's system.



  1   2   3   4   5   6


The database is protected by copyright ©essaydocs.org 2016
send message

    Main page