In php, js verifies the registration conditions and displays Chinese garbled characters when prompted.

In php, js verifies the registration conditions and displays Chinese garbled characters when prompted. js files are written separately. simple information filled in during login verification. for example, the registration name length must be greater than 6 characters, the mailbox format is correct, but the prompt information displayed on the div layer is garbled. how can this problem be solved? Figure .. I hope you will give me more advice .. Thank you... you cannot see the graph. You need to implement unified encoding. in php, the registration conditions are verified by js, and Chinese garbled characters are displayed when information is prompted.
Js files are written separately, and simple information is entered during login verification. for example, the length of the registration name must be greater than 6 characters, and the email format is correct, but the prompt information in the div layer is garbled. how can this problem be solved? Figure .. I hope you will give me more advice .. Thank you...

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You cannot see the image. It's okay if you want to unify the codes.
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You have changed the encoding of all files including js files to UTF-8.
Editplus is the page encoding, and dw is the page attribute.
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