Solutions to garbled JavaScript and alert Problems

Js files that can be used normally the other day. After some items are added, the prompt box in the alert () dialog box is always garbled with Chinese characters. I have read a lot on the Internet, basically, the answer is to add <meta http-equiv = "Content-Type" content = "text/html; charset = gb2312"/> or replace gb2312 with UTF-8, I have been using multiple methods for a long time and have not been able to solve this problem.

Solution:
Finally, I found something in a corner of a Forum. I used to specify the character set encoding method when referencing js files in html, the specific method is <script charset = "gb2312" language = "javascript" type = "text/javascript" src = "ntkoocx. js "> </script>. It's strange. Why didn't we get garbled in the past ?......