Validating Zero

Required validation triggers if my select returns number 0.

Setting custom validation rules don’t trigger when using setValue if I pass it number 0

register(
            {
                name: 'myProp'
            },
            {
                 required: 'whoops'
             }
        );

This triggers if setValue('myProp', 0, true);

Additionally

register(
            {
                name: 'myProp'
            },
            {
                 required: 'whoops',
                 validate: (id: number) => {
                       return (id > -1 && id !== 999) || 'whoops';
                  }
             }
        );

The validate function isn’t even called if I use setValue('myProp', 0, true);

I would expect the validate function to run every time there is an update. Also, how should 0 values be used? Selects might legitimately return the number 0.

The ideal solution would be a property which allows 0 as valid?

A quick fix is to cast everything as strings 😦

Any help is appreciated 😃

[sidonaldson]

Thank you for the super fast response Bill!

As i’m using MUI and the select seems to need an empty string to be ‘clean’ i’m setting a defaultValue of an empty string.

const { register, unregister, setValue, watch, errors, handleSubmit } = useForm<FormState>({
        defaultValues: {
            InputName: '',
        }
    });

Therefore for me the validation was super simple - removing required was the key.

register(
            {
                name: 'InputName'
            },
            {
                validate: (id: number | string) => {
                   return id !== '' || 'whoops';
            }
);

Is this covered in the docs and I missed it? Happy to do a PR otherwise

[bluebill1049]

I am going to close this issue for now, i will let you know what to update on documentation later on if you still interested 😃 👍