Why are many site usernames not allowed to start with numbers? Password is not allowed to start and end with a space? Is this a technical reason??

I don't think it is necessary at all.

Reply content:

I don't think it is necessary at all.

The reason why you should not start with a space is to avoid accidental loss.

How do you differentiate between full-width spaces and half-width spaces?

The number of spaces is difficult to check

The general space will be filtered out at the beginning of the end.

When your service supports mobile phone number login, you know why.

And uid this thing conflict. General Address bar Enter the UID to see some user information. If the user name is also the full number, then the system does not know whether the user name or UID. Back-end logic processing is also relatively cumbersome.

That's why many website usernames don't allow numbers to start with? Password is not allowed to start and end with a space? Is this a technical reason?? For more information, please pay attention to topic.alibabacloud.com (www.php.cn)!

