XAF - Validation Module Enhancements for Windows and the Web (Coming soon in v15.2)

In our upcoming release of the eXpressApp Framework, data validation occurs immediately after input focus changes when validation rule evaluation does not require querying additional data from the server. These rules are RuleRequiredField,RuleRegularExpressionRuleStringComparisonRuleValueComparison and RuleRange.

In-place validation is enabled for the Save context by default. To enable it for other contexts, use the AllowInplaceValidation property of the Validation | Contexts | Context node in the Model Editor.

Since rule evaluation occurs on the client side, in-place validation does not occur when:

The asterisk (*) symbol is automatically appended to an editor label when the RuleRequiredField is applied.

In-place validation engine relies on Controllers provided in our platform-specific ValidationWindowsFormsModule and ValidationAspNetModule components.

Note: The ASP.NET module was introduced in v15.2. In order to use in-place validation after upgrading your existing ASP.NET applications to v15.2, be certain to add  this module from the Toolbox into the Application Designer.


The XAF Team would love your feedback. Please tell us what you think of these new features.

8 comment(s)
Alex Miller

Hello Dennis,

This is great! Is the 'asterisk (*) symbol' optional? I'd rather have some sort of conditional formatting on required fields.



24 November, 2015
Nate Laff

I'll be blunt. I hate the automatic asterisk on RuleRequiredFields. Should be optional, and disabled by default.

24 November, 2015
JeePee [NL]

I prefer a bold label instead of an asterisk added to the label��

24 November, 2015
Vincent Micallef Decesare

Hi Dennis,

Love the client-side validation, it will make our applications look more professional.

However, when it comes to the asterisk I'd prefer if we had an option to switch it off at will. Reason being that we already implemented similar behavior ourselves(our users requested italic text style for labels of the required fields). As Alexandre Miller already mentioned, some conditional formatting would be a neater solution. Also, does it take 'TargetCriteria' into consideration?

Thanks and keep up the good work

25 November, 2015
Dennis (DevExpress Support)

Thanks for your comments, guys. Sure, you can easily remove the required field mark from the layout label by setting the string RequiredFieldMark property under the Options | LayoutManagerOptions node in the Model Editor.

As for styling such labels (bold, italic) or even highlighting the editors themselves, we appreciate your feedback and will take it into account.

25 November, 2015
Dennis (DevExpress Support)

@Vincent: The TargetCriteria parameter is not currently considered and this mark is always displayed in the layout. We will take your request into account as well.

25 November, 2015
Gerhard Achrainer

Hi Dennis,

this is a great enhancement to the validation system. Like others, we have our own styling for required fields (red labels).

May I suggest to have the same flags that we see in the ConditionalAppearance module for the RequiredFieldMark (FontColor, FontStyle, BackColor)?



25 November, 2015
Dennis (DevExpress Support)

@Gerhard: Thanks for your suggestion!

25 November, 2015

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