二重送信防止
https://codezine.jp/article/detail/769
https://qiita.com/tabo_purify/items/7d47656bd7c6332efe8a
https://www.php-factory.net/trivia/18.php
js アラート コンフォーム
http://uxmilk.jp/14032
http://www.tagindex.com/javascript/window/confirm.html
js フォームアシスト
https://www.showcase-tv.com/formassist/
https://www.showcase-tv.com/smartphone-efo/
eclips インスペクション「ｘｘを変数に解決できません」と表示されてしまいます
chrome jsデバッグ
https://qiita.com/snoguchi/items/8f6bb62a3166eca23ac3
http://www.koikikukan.com/archives/2013/07/31-005555.php
http://www.koikikukan.com/archives/2013/07/31-005555.php
jQuery ページ遷移
http://uxmilk.jp/41457
http://www.okapiproject.com/java/java_tools/eclipse/vol_2/eclipse_cvsfuncion.htm
javascript 型比較
https://qiita.com/south37/items/c8d20a069fcbfe4fce85
https://qiita.com/amamamaou/items/ef0b797156b324bb4ef3
jQuery length
http://www.jquerystudy.info/reference/miscellaneous/length.html
js parseInt()
https://developer.mozilla.org/ja/docs/Web/JavaScript/Reference/Global_Objects/parseInt
https://developer.mozilla.org/ja/docs/Web/JavaScript/Reference/Global_Objects/String/length