Required

The required rule is the only validator that fails on empty input. Every other rule validates the value when present, so a field must opt into being mandatory.

What it checks

The value is not empty. Empty means:

• "" (empty string)
• null
• undefined
• empty arrays []

Config flag

validationSchema: {
  name: { required: true },
}

With a custom message (v1 style requiredMessage also works):

validationSchema: {
  name: { required: true, requiredMessage: "Please enter your name" },
}

V builder

import { V } from "formify-js";

V.required()                    // default message
V.required("Please enter a name")

Default message

This field is required

Things to know

• Combine with any other rule to make an optional field mandatory: { required: true, email: true } requires a valid email.
• The per-field message override takes precedence: { message: { required: "..." } }.