#Form field types

The builder offers input fields, selections, display elements and containers; each input field stores one value under its key, and display elements and containers store nothing.

#From field to process data

flowchart LR
  F["Form of the user task<br/>Activity_review"] --> T["Text field 'comment'"]
  F --> C["Checkbox 'approved'"]
  F --> P["File picker 'invoice'"]
  T --> D1["Activity_review.comment<br/>text"]
  C --> D2["Activity_review.approved<br/>true / false"]
  P --> D3["Activity_review.invoice<br/>a file reference"]

When the person completes the task, each input field's value is stored under the task's element id and the field's Key. See Work with process data.

#Input

Field	What the person does	Value in the process data
Text field	Types a line of text	Text
Text area	Types several lines	Text
Number	Types a number	Number
Date time	Picks a date, a time, or both	Text, such as `2026-09-30`; empty is `null`
File picker	Chooses one file, or several with Multiple	A file reference, or a list of them

#Selection

Field	What the person does	Value in the process data
Checkbox	Ticks one box	`true` or `false`
Checkbox group	Ticks several options	A list of the picked values
Radio group	Picks one option	The picked value
Select	Picks one option from a drop-down	The picked value
Tag list	Picks several options as tags	A list of the picked values

The options are either typed into the field's settings, or come from the process through Option data on the user task — see Fill a form with process data.

For every selection, __display holds the label that was picked, next to the value. ⚠️ For a checkbox group and a tag list, __display holds the values, not the labels.

#Presentation

Text view, Image view, HTML view, Document preview, Table, Spacer and Separator show something but store nothing. Their content can be fixed in the builder, or filled from the process — a text, an image, a file or table rows. See Fill a form with process data.

⚠️ A Table only shows rows; the person cannot edit them.

#Containers

Group — puts fields together under a heading. The fields still store their values under their own keys.
Dynamic list — a set of fields the person can add again and again, one row each. Its value is a list with one object per row.

⚠️ A dynamic list's key is generated, such as dynamiclist_ab12, and cannot be changed in the builder. Use that key to read the list in later steps.

#Validation in the form

Required fields, lengths, patterns and number ranges are checked in the browser when the person submits. ⚠️ They are not checked again when the task arrives — rules that must hold belong in a gateway after the task.

#Files

A file chosen in a file picker is uploaded when the person submits the form, and later steps receive a reference to it. ⚠️ Nothing in Chester limits the size of an upload; the server the Execution app runs on may refuse very large files.