# About embedded variables

Embedded variables allow you to show values that change dynamically at runtime. Put placeholders in strings where the embedded variable will be shown. At run time, the placeholder is updated with the real-time values of the variables.

Embedded variables are of two kinds:

- A tag is read to provide the run-time value. Use tags, to embed tag values (Numeric or String), date values, and time values. The tag is read at run time and the current value is shown.
- A tag is not read. Use this type to embed literal strings and numbers that will be shown at run time as they were entered.

Use one or more embedded variables in:

- The text captions on graphic objects
- The title bar of On Top displays
- Message text.

For example, you could embed a tag value and the time variable in a local message. At run time when the local message is shown, it is updated to reflect the tag’s current value as the value changes. The time is also updated as the time changes.

You can also use literal strings and constants in embedded variables, or a combination of both variable and literal strings and numbers.

Embedded variables can consist of:

- Numeric (analog or digital) tags, including both HMI and data server tags
- Literal numbers (constants)
- String tags, including both HMI and data server tags
- Literal strings (static text)
- Tag placeholders.
- The time
- The date

## Use literal strings instead of tag values

To use a character string in an embedded variable instead of a tag value, choose the Literal string option in the String Variable dialog box. To use a literal number instead of a tag value, choose the Literal number option in the Numeric variable dialog box.

Tip: | You can include numbers in the Literal string option. Use the Literal number option if the number you want to display requires decimal places or other special formatting.

## Use tag placeholders instead of tag names

The Graphics editor accepts tag placeholders instead of tag names. Placeholders allow you to use the same display with different sets of tags.

You can use tag placeholders in:

- The graphic display that opens when the application is first run.
- Graphic displays that are opened using a goto display button.
- Graphic displays that are opened using a display list selector.
- The graphic display that opens when the logout button is pressed.
- The graphic display that opens when auto logout is used.
- Graphic displays that are opened using the Remote Display Number global connection.
- Parameter lists for parameter passing.

Use parameter files or parameter lists to specify which tags to substitute for which placeholders.

## To create a tag placeholder in an embedded variable

- In the Tag box, type the cross-hatch character followed by a number (no space in between). For example, #1.

## To delete an embedded variable

- Click the embedded variable to select it, and then press Delete.

  Tip: | Embedded variables are case sensitive, and must be in the proper format and syntax to work. If you make a mistake, your variable will be treated as a piece of text. Therefore, do not attempt to edit embedded variables manually. Use the Insert Variable and Edit variable dialog boxes to avoid problems.

## See also

Embed a variable in a message

Embed a variable in a caption

Insert a string variable

Insert a time/date variable

Insert a numeric variable

Keywords: embedded variable