A quick tip, as it’s been a while since my last post..
The ShowMandatory property for fields on a page object is helpful for drawing the user’s attention to required fields on a page.
If a field is not populated on a page and the ShowMandatory property for that field is set to true, then a red asterisk (*) will appear:
The problem is, for number based fields which default to 0, this field is actually populated so the asterisk will not show up.
Luckily there is an easy solution; to show integer or decimal fields as mandatory we can also set the field’s BlankZero field to true:
pageextension 50000 "Item Card DK" extends "Item Card"
{
layout
{
modify("Net Weight")
{
BlankZero = true;
ShowMandatory = true;
}
}
If you have more complex (or fringe) requirements, such as numbers must be positive, there is also the BlankNumbers page field property. BlankNumbers can be set to the following values:
| Value | Description |
|---|---|
| DontBlank (default) | Not clear any numbers |
| BlankNeg | Clear negative numbers |
| BlankNegAndZero | Clear negative numbers and zero |
| BlankZero | Clear numbers equal to zero |
| BlankZeroAndPos | Clear positive numbers and zero |
| BlankPos | Clear positive numbers |
Note: BlankNumbers is not available when modifying fields from a pageextension object, you can only use this property on a field declaration.
Dan Kinsella's Blog 