Guide 10 · Developer docs

Building forms with the Forms module: how a form is put together and placed on a page, validating and branching, presenting it, where submissions are stored, and what happens after one arrives, from jobs and records to CRMs and payments.

L1–L2

Unit 03 of 07 1 page

Branching forms

Updated 23/10/2026 01:43

Showing, hiding and requiring fields, groups and steps as a visitor answers earlier ones, and the patterns that keep the browser and the server agreeing about what a form needs.

A browser evaluates a form's conditions as the visitor types; the server evaluates the same rules only once, on submit. This unit covers the condition types, the three levels they apply at (field, group and step), and the patterns that keep the browser and the server in agreement as a branching form grows.

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01 Conditional logic Showing, hiding and requiring fields, groups and steps as the visitor answers. The browser applies the rules as the visitor types and the server applies them on submit; these patterns give the same result on both. The safe patterns, and how to keep a branching form maintainable.

Objects ReferenceGenerated from the platform, so it is always current

API ReferenceEvery REST endpoint, in cURL, PHP, Python and JavaScript

Branching forms

In this unit