Examples & RecipesRecipe Library
Calculate field values and format strings live
Automatically calculate prices, format reference codes, and transform field values in real time without custom JavaScript functions.
Automatically calculate prices, format reference codes, and transform field values in real time without custom JavaScript functions.
Use this when
- build reactive form transforms that survive Cloud schema sync
- compute field values without writing raw JavaScript functions
- calculate status-based pricing or conditional totals declaratively
- format reference codes or IDs from sibling inputs in real-time
Dyrected concepts
admin.hooks.onChange, when.then, when.match, when.sibling, when.concat, when.slugify
Additional packages: No additional packages.
Decisions and cautions
Use this recipe only when its runtime matches the project you are documenting or building. Cloud recipes must stay inside the managed content backend boundary. Self-hosted recipes may use the server runtime, database, hooks, and infrastructure you control.
Complete recipe
This is the canonical source compiled and behavior-tested by @dyrected/knowledge.
import {
defineCollection,
defineNumberField,
defineSelectField,
defineTextField,
expr,
} from "@dyrected/core";
export const Invoices = defineCollection({
slug: "invoices",
fields: [
defineTextField({
name: "title",
label: "Invoice Title",
required: true,
}),
defineTextField({
name: "slug",
label: "Slug",
required: true,
admin: {
hooks: {
onChange: expr.ifElse(
expr.empty("value"),
expr.slugify("siblingData.title"),
"value"
),
},
},
}),
defineSelectField({
name: "planTier",
label: "Plan Tier",
defaultValue: "standard",
options: [
{ label: "Free Trial", value: "trial" },
{ label: "Standard", value: "standard" },
{ label: "Enterprise", value: "enterprise" },
],
}),
defineNumberField({
name: "basePrice",
label: "Base Price (₦)",
admin: {
readOnly: true,
hooks: {
onChange: expr.match()
.case(expr.sibling("planTier").equals("trial"), 0)
.case(expr.sibling("planTier").equals("standard"), 25000)
.case(expr.sibling("planTier").equals("enterprise"), 100000)
.otherwise(25000),
},
},
}),
defineTextField({
name: "referenceCode",
label: "Payment Reference",
admin: {
readOnly: true,
hooks: {
onChange: expr.concat(
"INV-",
expr.upper("siblingData.planTier"),
"-",
expr.slugify("siblingData.title")
),
},
},
}),
],
});