Laravel 5.3 Validation Fails when Variables are Null

问题

Since upgrading laravel from 5.1 to 5.3, I've got couple of odd issues with Validation.

When I post a data like this:

firstName    null

And the validation rules are like this:

$validator = Validator::make($postData, [
              'firstName'           => 'string|max:255',
              'lastName'            => 'string|max:255'
            ]);

The above fails with the messages something like "The XYZ must be a string.". What I don't understand is:

1. Why is the validation failing when it is not set as required? Meaning, it should ignore it and not throw an error if the value is empty, right?

2. Why does the validation fail if the value is set as null?

3. Why does the validation fail when the parameter is not sent at all? (like the lastName which is not posted at all)

Has something changed in Laravel 5.3 validations?

回答1:

Add nullable rule:

'firstName' => 'string|max:255|nullable',
'lastName' => 'string|max:255|nullable'

The field under validation may be null. This is particularly useful when validating primitive such as strings and integers that can contain null values.

来源：https://stackoverflow.com/questions/40465297/laravel-5-3-validation-fails-when-variables-are-null