Typographical Conventions

To indicate the various syntactic components of ActionScript, this book uses the following conventions:

Menu options

Menu options are shown using the character, such as File Open.

Constant width

Indicates code samples, clip instance names, frame labels, property names, and variable names. Variable names often end with the standard suffixes that activate code-hinting (such as _mc for variables that refer to movie clip instances). Although using these suffixes is considered the best practice, for brevity or clarity, the preferred suffixes have sometimes been omitted.


Indicates function names, method names, class names, layer names, symbol linkage identifiers, URLs, filenames, and file suffixes such as .swf. In addition to being italicized, method and function names are also followed by parentheses, such as duplicateMovieClip( ).

Constant width bold

Indicates text that you must enter verbatim when following a step-by-step procedure, although it is sometimes used within code examples for emphasis, such as to highlight an important line of code in a larger example.

Constant width italic

Indicates code that you must replace with an appropriate value (e.g., your name here). Constant width italic is also used to emphasize variable, property, method, and function names referenced in comments within code examples.

When referring to properties and methods of objects and classes, I use these conventions:

  • Class-level (static) properties are shown with the both the class name and property in constant width because they should both be entered verbatim. For example, Stage.width or Math.NaN.

  • Instance-level properties are shown with the class or object instance in constant width italic because it should be replaced by a specific instance. The property itself is shown in constant width and should be entered as shown. For example, Button .tabEnabled.

  • Method and function names, and the class or object to which they pertain, are always shown in italics and followed by parentheses, as in MovieClip.duplicateMovieClip( ). Refer to the online help or ActionScript for Flash MX: The Definitive Guide to know whether to include the class name literally (i.e., if it is a so-called static method), as in TextField.getFontList( ), or replace it with an instance name, such as ball_mc.duplicateMovieClip( ).

  • For brevity, I often omit the class name when discussing a property or method of a class. For example, if discussing the htmlText property of the TextField class, when I say “set the htmlText property,” you should infer from context that I mean, “set the someField_txt .htmlText property, where someField_txt is the identifier for your particular text field.”

  • In some cases, an object property will contain a reference to a method or callback handler. It wasn’t always clear whether I should have used constant width to indicate that it is a property (albeit one storing a method name) or italics and parentheses to indicate it is a method (albeit one stored in a property). If the line between a property referring to a method versus the method itself is sometimes blurred, forgive me. To constantly harp on the technical difference would have made the text considerably less accessible and readable.

Pay special attention to notes and warnings set apart from the text with the following icons:


This is a tip. It contains useful information about the topic at hand, often highlighting important concepts or best practices.


This is a warning. It helps you solve and avoid annoying problems or warns you of impending doom. Ignore at your own peril.

Get Actionscript Cookbook now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.