There are three types of built-in variables that were designed for different purposes in Setup Factory. The first type are called Global variables that are expanded once at the beginning of the setup. These variables were designed to be used in action script for common values that might differ between systems.

The second type of built-in variable are called Session variables. This type was designed to be used for values that may change during the installation process. They are most commonly used to display dynamic content on screens and use as file destinations.

The third type of built-in variable are called Design-time constants. While the previous two types are expanded at run time, design-time constants are expanded during the build process. Normally this type is used for settings such as the product version, or dates of the build etc.

A list of the available built-in variables can be found in each of the following categories:

Tip: Often global variables are used as part of a full path where you need to join two strings together. For example, you may need a path consisting of the user's Program Files folder and a program folder such as "ApplicationX." To do this, you would use the string concatenation operator which consists of two dots (..). The script looks like this:

_ProgramFilesFolder .. "\\ApplicationX"

You can also use the String.Concat action to concatenate two strings.

Note: There are also a series of actions available that can be used to gather information about the user's system that may not be part of the built-in variables list. For example, additional common folder paths can be read using the Shell.GetFolder action. There is also a System category of actions for other system information.

For more information on variables, see Variables in the Scripting Guide.