Summary: In this lesson, you will learn how to create string controls and indicators.
A string is a sequence of displayable or non-displayable ASCII characters. Strings provide a platform-independent format for information and data. Some of the more common applications of strings include the following:
On the front panel, strings appear as tables, text entry boxes, and labels.
Use the string control and indicator located on the
Controls>>Text Controls and Controls>>Text
Indicators palettes to simulate text entry boxes and
labels. Use the Operating tool or Labeling tool to type or
edit text in a string control. Use the Positioning tool to
resize a front panel string object. To minimize the space that
a string object occupies, right-click the object and select
the Visible Items>>Scrollbar option from the
shortcut menu.
Right-click a string control or indicator on the front panel to select from the display types shown in the following table. The table also shows an example message for each display type.
| Display Type | Description | Message |
|---|---|---|
| Normal Display | Displays printable characters using the font of the control. Non-printable characters generally appear as boxes. There are four display types. |
There are four display types. \ is a
backslash.
|
| '\' Codes Display | Displays backslash codes for all non-displayable characters. |
There\sare\sfour\sdisplay\stypes.\n\\\sis\sa\sbackslash.
|
| Password Display | Displays an asterisk (*) for each character including spaces. |
***************************** *****************
|
| Hex Display | Displays the ASCII value of each character in hex instead of the character itself. |
5468 6572 6520 6172 6520 666F 7572 2064 6973 706C 6179
2074 7970 6573 2E0A 5C20 6973 2061 2062 6163 6B73 6C61
7368 2E
|
Use the table control located on the Controls>>All
Controls>>List & Table palette or the Express
Table VI located on the Controls>>Text
Indicators palette to create a table on the front
panel. Each cell in a table is a string, and each cell resides
in a column and a row. Therefore, a table is a display for a
2D array of strings. The illustration in Figure 1
shows a table and all its parts.
![]() |
Define cells in the table by using the Operating tool or the
Labeling tool to select a cell and typing text in the selected
cell.
The table displays a 2D array of strings, so you must convert 2D numeric arrays to 2D string arrays before you can display them in a table indicator. The row and column headers are not automatically displayed as in a spreadsheet. You must create 1D string arrays for the row and column headers.
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