当变量为空时 Laravel 5.3 验证失败
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Laravel 5.3 Validation Fails when Variables are Null
提问by Neel
Since upgrading laravel from 5.1 to 5.3, I've got couple of odd issues with Validation.
自从将 laravel 从 5.1 升级到 5.3 以来，我在验证方面遇到了一些奇怪的问题。
When I post a data like this:
当我发布这样的数据时：
firstName null
And the validation rules are like this:
验证规则是这样的：
$validator = Validator::make($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:
以上失败，消息类似于"The XYZ must be a string.". 我不明白的是：
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?Why does the validation fail if the value is set as
null?Why does the validation fail when the parameter is not sent at all? (like the
lastNamewhich is not posted at all)
为什么未设置为时验证失败
required？意思是，如果值为空，它应该忽略它并且不会抛出错误，对吗？如果将值设置为 ，为什么验证会失败
null？为什么在根本不发送参数时验证失败？（就像
lastName根本没有发布的）
Has something changed in Laravel 5.3 validations?
Laravel 5.3 验证中有什么变化吗？
回答by Alexey Mezenin
Add nullablerule:
添加nullable规则：
'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 containnullvalues.
验证中的字段可能是
null。这在验证可包含null值的字符串和整数等原语时特别有用。
