Skip to content

Formula Reference

Useful formula patterns for Versaa form calculated fields, visibility conditions, and value formulas. All formulas run as single-line JavaScript expressions.

General Rules

  • All Versaa formulas must be single-line JavaScript expressions — no const, let, var, or multi-line blocks.
  • Reference form items via $formItem.FieldName.
  • Formulas that chain through two or more reactive dependencies may not re-evaluate correctly — calculate directly where possible.
  • When prompting an LLM for formula help, specify: "as a one-liner, minimal abstraction, no const declarations".

Null Coalescing / Default Values

// Use empty string if field is null or empty
($formItem.FieldName || "")

// Use 0 if field is null or empty
($formItem.FieldName || 0)

// Conditional with fallback
($formItem.SomeField ? $formItem.SomeField : "Default Text")

Concatenation

// Simple string join
$formItem.FirstName + " " + $formItem.LastName

// With null safety
($formItem.FirstName || "") + " " + ($formItem.LastName || "")

// Multi-field concatenation
$formItem.AddressLine1 + ", " + $formItem.AddressLine2 + ", " + $formItem.Town + ", " + $formItem.Postcode

Date Calculations

// Current date (use the built-in function)
Current_Date

// Age from date of birth (years)
(new Date().getFullYear() - new Date($formItem.DateOfBirth).getFullYear())

// More accurate age (accounting for month/day)
(new Date().getFullYear() - new Date($formItem.DateOfBirth).getFullYear() -
 (new Date().getMonth() < new Date($formItem.DateOfBirth).getMonth() ||
  (new Date().getMonth() === new Date($formItem.DateOfBirth).getMonth() &&
   new Date().getDate() < new Date($formItem.DateOfBirth).getDate()) ? 1 : 0))

// Days between two dates
Math.floor((new Date($formItem.EndDate) - new Date($formItem.StartDate)) / (1000 * 60 * 60 * 24))

// Percentage through lifecycle (from install date and lifespan in years)
(Math.floor((new Date() - new Date($formItem.InstallDate)) / (1000 * 60 * 60 * 24 * 365.25)) / ($formItem.LifeSpan || 1) * 100)

String Splitting (Pipe/Delimiter)

Useful for parsing SQLite builder+parser output:

// Split pipe-delimited string — get first segment
($formItem.z_QueryOutput ? $formItem.z_QueryOutput.split("|")[0] : "")

// Get second segment
($formItem.z_QueryOutput ? $formItem.z_QueryOutput.split("|")[1] : "")

// Get first comma segment from second pipe segment (CRM Class Level 1)
($formItem.z_QueryOutput ? $formItem.z_QueryOutput.split("|")[1].split(",")[0] : "")

Current User

// Get current logged-in user's display name
this.UserDisplayName()

Warning: The name returned by UserDisplayName() may be the app name, AD stored name, or backend name depending on configuration. Test in context before relying on it.

Conditional / Ternary

// Basic ternary
($formItem.SomeFlag == "Yes" ? "Shown text" : "Hidden text")

// Nested ternary
($formItem.Status == "Active" ? "Active" : ($formItem.Status == "Pending" ? "Pending" : "Unknown"))

// Check if field has a value
($formItem.FieldName ? "Has value" : "Empty")

Arrow Functions

Arrow functions can be used within a single-line expression for map/filter/reduce operations:

// Map over an array (if field contains array data)
$formItem.Items.map(x => x.Name).join(", ")

// Filter and count
$formItem.Items.filter(x => x.Status == "Active").length

Regex Patterns

National Insurance Number

^((A[A-BEHKLMPRSTWX-Z])|(B[A-BEHKLMT])|(C[A-BEHKLR])|(E[A-BEHKLMPRSTWXYZ])|(GY)|(H[A-BEHKLMPRSTWXYZ])|(J[A-BCEGHJKLMNPRSTWXYZ])|(K[A-BEHKLMPRSTWXYZ])|(L[A-BEHKLMPRSTWXYZ])|(M[AWX-X])|(N[A-BEHLMPRSWXYZ])|(O[A-BEHKLMPRSX])|(P[A-BCEGHJLMNPRSTWXY])|(R[A-BEHKMPRSTWXYZ])|(S[A-BCGHJKLMNPRSTWXYZ])|(T[A-BEHKLMPRSTWXYZ])|(W[A-BEKLMP])|(Y[A-BEHKLMPRSTWXYZ])|(Z[A-BEHKLMPRSTWXY]))\d{6}([A-D]|s)$/gm

UK Telephone Number

^(?:(?:0(?:0|11)\s?|+)44\s?(?:0\s?)?|0)(?:\d{2}\s?\d{4}\s?\d{4}|\d{3}\s?\d{3}\s?\d{3,4}|\d{4}\s?(?:\d{5}|\d{3}\s?\d{3})|\d{5}\s?\d{4,5}|8(?:00\s?11\s?11|45\s?46\s?4\d))$

Group Filtering

To filter a data grid group to show only rows matching a condition:

  • Use the Group Filter property on the GroupDataGridElement
  • The filter expression is a JavaScript boolean, same syntax as other formulas
  • Example: show only "Active" components:
$item.Status == "Active"