import React from 'react'; import { useForm, useWatch, useFieldArray, Controller, Control, UseFormReturn, } from 'react-hook-form'; let renderCount = 0; type FormInputs = { data: { name: string; conditional: string }[]; }; const ConditionField = ({ control, index, unregister, }: { control: Control; unregister: UseFormReturn['unregister']; index: number; fields: T; }) => { const output = useWatch({ name: 'data', control, }); React.useEffect(() => { return () => { unregister(`data.${index}.conditional` as const, { keepDirty: true, keepTouched: true, }); }; }, [unregister, index]); return output?.[index]?.name === 'bill' ? ( ) : null; }; const UseFieldArrayUnregister: React.FC = () => { const { control, handleSubmit, register, unregister, setValue, getValues, formState: { isDirty, touchedFields, dirtyFields, errors }, } = useForm({ defaultValues: { data: [{ name: 'test' }, { name: 'test1' }, { name: 'test2' }], }, mode: 'onSubmit', }); const { fields, append, prepend, swap, move, insert, remove } = useFieldArray({ control, name: 'data', }); const [data, setData] = React.useState(); const updateFieldArray = () => { setValue('data', [...getValues().data, { name: 'test', conditional: '' }]); }; renderCount++; return (
{ setData(data); })} >
    {fields.map((data, index) => (
  • {index % 2 ? ( ) : ( ( )} control={control} rules={{ required: 'This is required', }} name={`data.${index}.name`} data-order={index} /> )} {errors.data?.[index]?.name && (

    {errors.data[index]!.name!.message}

    )}
  • ))}
{renderCount}
{JSON.stringify(data)}
{isDirty ? 'yes' : 'no'}
{JSON.stringify(dirtyFields)}
{JSON.stringify(touchedFields.data)}
); }; export default UseFieldArrayUnregister;