https://b.hatena.ne.jp/entry/s/www.w3resource.com/javascript/form/ip-address-validation.php JavaScript: HTML Form - IP address validation Last update on August 19 2022 21:50:37 (UTC/GMT +8 hours) Every computer connected to the Internet is identified by a unique four-part string, known as... https://b.hatena.ne.jp/qxd/20210310#bookmark-4669556162378584738 2021-03-09T16:56:57Z https://b.hatena.ne.jp/snaka72/20151203#bookmark-272661737 2015-12-03T05:36:05Z