Customize Expression Builder
You can customize Expression Builder in the following ways:
- Manage the list of built-in functions displayed in Expression Builder, removing unwanted functions or changing the function groups.
- Create your own functions and make them available in the Expression Builder wizard.
The function groups are defined in an XML file called QuickFields_Functions.xml. This file stores a list of the currently available functions in the filtered groups. To change the groups or move or remove functions, you can edit this XML file in any text editor.
![Note Note](rsrc/note.png)
There must be at least one group in the XML file.
The Quick Fields feature is written as a JScript ArcPad applet. You can add your own JScript functions that can be used in Expression Builder. To add your own functions, open the QuickField_Functions.js in ArcPad Studio (or your favorite editor) and follow these basic principles:
- Each function name must be prefixed with _ap. For example, creating a new name function would be called _apMyNewName().
- The value you require to populate the field must be set to g_Value. For example, g_Value = “ArcPad Rocks”.
The follow table shows a list of the functions contained in each of the default function groups, and an example of the output that each function would deliver in your edit form.
Function group | Function name | Example output |
---|---|---|
Points | Shape X Shape Y | -138 34 |
Polylines | Length | 256.65 |
Polygons | Perimeter Area | 72.3 1248.44 |
GPS | GPS X Coord GPS Y Coord GPS pDOP GPS hDOP GPS UTC Time GPS Estimated Precision Error GPS Number of Satellites | 17.2356 -56.4415 -1.79769313486232E+308 5.3 05/04/13 03:01:19 1.#QNAN (Garmin Receivers only) 6 |
Date Time | Date Date Time Day Month Full Year Day String Month String Hours Minutes Seconds Time String | Day of the month (from 1-31) 14:33 from 0-6 from 1-12 four digits - 1978 Monday January from 0-23 from 0-59 from 0-59 14:44 |
System | User Name Unique ID Sequential ID Incremental ID | System Login - Roxanne 12548 123, 124, 125… 1,2,3... |