Lowercase

The lowercase rule validates that every letter in a value is lowercase.

Configuration

validationSchema: {
  whisper: { lowercase: true },
}

With a custom message:

whisper: { lowercase: "Use lowercase letters only" }

V builder

import { V } from "formify-js";

V.lowercase()
V.lowercase("Use lowercase letters only")

Default message

Must be in lowercase

Examples

Things to know

• This is an all-letters-lowercase check, not a "contains one lowercase" check — for the latter use containsLowercase.
• Empty values pass unless required: true is also set.