# Parameter file and parameter list

When you open a graphic display that has tag placeholders, you specify a parameter file or a parameter list that will supply tag names or parts of tag names for the tag placeholders. This lets you use different sets of tags with a single graphic display.

Parameter list and parameter file work in the same way, replacing tag placeholders with actual tags at run time. The difference between them is that a parameter file is created as a separate file and is referenced by the graphic objects and displays that use it, while a parameter list is created with the object properties and remains with the displays and objects. If you copy displays that use parameter files from one application to another, you must also copy the associated parameter files. If you copy displays that use parameter lists, the lists are copied with the displays and their objects.

A parameter file can reference up to 500 placeholders. Use parameter files for displays that require large numbers of placeholders, and parameter lists for displays with only a few placeholders.

Use parameter file or parameter list to replace placeholders in:

- The graphic display that opens when the application is first run. Specify the graphic display to open, and the parameter file or parameter list to use with it, in the Startup editor.
- Graphic displays that are opened using a Goto Display button, Logout button, or Display List Selector. Specify the graphic display to open, and the parameter file or parameter list to use with it, when you set up the button or selector.
- The graphic display that opens when the Logout button is pressed to log the user out.
- The graphic display specified on Runtime tab of the Project Settings dialog box when auto logout is enabled.
- Graphic displays that are opened using the Remote Display Number global connection. Specify the display on the Display tab of the Global Connections editor.

When the graphic display opens at run time, the application substitutes the string specified in the parameter file or parameter list for the tag placeholders on the graphic display.

## See also

Tag placeholders

Configure startup settings

Specify project setting (Runtime tab)

Set up global connections - Display tab

Use tag placeholders