File Upload

The File Upload element lets people attach one or more files to a form, by drag and drop or with a file picker.

The File Upload element enables users to attach one or more files directly within a form. It is deeply integrated with Procesio's file handling capabilities, meaning uploaded files flow naturally into process variables and can be processed, stored, or forwarded by downstream actions in the workflow.

You have full control over what users can upload: specify allowed file extensions (allowedfiletypes), enforce a maximum file size (maxfilesize), and optionally allow multiple files in a single upload field (allowmultiplefilesupload). The current file or files are accessible at runtime via the value attribute, enabling you to inspect, validate, or respond to uploads from event-driven logic.

Adding files

The person filling the form can add files in two ways:

drag files from their computer and drop them on the upload area, or
click Select file and pick the files.

With Allow multiple files upload on, they can add several files to the same field. You can attach the same file more than once in a form.

File size and type checks

Max file size is in megabytes (500 by default) and applies to each file. Allowed file types lists the extensions people may upload; with no type selected, any file is allowed. The form checks both when it is submitted. If a file breaks a rule, a message shows under the field and nothing is sent:

"File size should be less than N MB" (or "Some file sizes should be less than N MB" for several files)
"File extension is not allowed." (or "Some file extensions are not allowed.")

What the form submits

A field that takes one file submits that file. A field with Allow multiple files upload on submits a list of files.

Key Use Cases

• Document upload for onboarding, contracts, or compliance forms

• Restricting uploads to specific types (e.g., PDF only, or images: jpg, png)

• Enforcing file size limits to prevent oversized uploads at the form level

• Collecting multiple supporting documents in a single upload field

• Reading the uploaded file reference at runtime to pass it to a process action

Runtime API — Attributes in Procesio Forms

All attributes below are accessible and modifiable at runtime via the element's data model in Procesio Forms — on any available event such as onLoad, onChange, or custom triggers.

API Name	Description	Type	Default	Notes
label	Display label for the upload field	string	—	—
tooltip	Help text shown alongside the label	string	—	—
description	Descriptive text displayed near the upload area	string	—	—
infotext	Supplementary info displayed below the element	string	—	—
value	Current uploaded file(s) — accessible at runtime	file\|file[]\|null	—	—
readonly	View-only — user cannot upload new files	boolean	false	—
disabled	Fully non-interactive	boolean	false	—
visible	Controls element visibility	boolean	true	—
allowmultiplefilesupload	Allows uploading more than one file	boolean	false	—
name	Unique element name	string	—	—
id	Unique element ID	string	—	—
required	A file must be uploaded to submit the form	boolean	false	—
maxfilesize	Maximum allowed file size	number\|null	500 MB	—
allowedfiletypes	List of permitted file extensions	string[]	all	e.g. ['pdf','docx']

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