<MESSAGE/> tag
Displaying correction notes
The rule definition is used by the template developer to define correction notes that are displayed in the form directly below the affected input component.
![](../../Dynamic-Forms/DE_validatoren_message.png)
These notes are defined in the rule using the <MESSAGE/> tag. The tag can only be used within the <VALIDATION/> section of a rule definition (see Subcategories of rule definition).
The following applies here:
- The <VALIDATION/> section of a rule is carried out only if the basic value determination returns <FALSE/>. The note is only displayed to the editor when a rule violation occurs.
- The note text always refers to a particular property of the form element. This means that a particular property of the form element is checked in the value determination area (e.g. “Is the input component empty?”) and this condition is then verified in the <VALIDATION/> section. It is necessary to add a <PROPERTY/> tag in both cases.
In addition to the ability to output a correction note using a <MESSAGE/> tag, it is also possible to use a CMS_LABEL type input component that is displayed or hidden as required.
Example
Rule displays a note when an input component is empty
In this example, a rule violation and a note are to be displayed in the form if an input component is empty.
For this purpose, the EMPTY property of the input component is checked within the <WITH/> section. If the input component is empty, the following expression returns the value TRUE:
<PROPERTY source="st_supplier" name="EMPTY"/>
<!-- returns TRUE if the input component is empty -->
To ensure that the <VALIDATION/> section is carried out when the input component is empty, the expression must be negated:
<NOT> <PROPERTY source="st_supplier" name="EMPTY"/></NOT>
<!-- returns FALSE if the input component is empty -->
The <VALIDATION/> section must then check the VALID property of the component:
<PROPERTY source="st_supplier" name="VALID"/>.
If the input component is empty, the <VALIDATION/> section runs, a rule violation is displayed and the (language-dependent) note is displayed in the form area. Once the editor fixes the incorrect input in the form, the note (and rule violation) are hidden again.
<ON_SAVE>
<WITH>
<NOT>
<PROPERTY source="st_supplier" name="EMPTY"/>
</NOT>
</WITH>
<DO>
<VALIDATION>
<PROPERTY source="st_supplier" name="VALID"/>
<MESSAGE lang="*" text="No supplier chosen!"/>
<MESSAGE lang="DE" text="Kein Lieferant ausgewählt!"/>
</VALIDATION>
</DO>
</ON_SAVE>
The note defined in the rule is also used to display the collected correction notes (see Figure).