Fix Lua Format String Error : Illegal Escape Character

0, problem description

invalid option '%{' to 'format'
invalid option '%;' to 'format'

This is the problem I've had with escaping CSS, but you might also:

invalid option '% (extra characters here)' to 'format'

similar error.

1. Solution

For a list of legal escape characters, refer to:

Lua string
https://www.runoob.com/lua/lua-strings.html

Therefore, this error will be reported when executing string.format() when it encounters % (text or symbol that is not an escape character).

Therefore, if a non-escaped character is added by mistake, it should be deleted;

If you need to enter a percent sign (%), it should be escaped:

Original: %
escape: %%

If the legal escape character is judged to be illegal, it is recommended to delete it and type it again with the keyboard:

Original character: %О (Note, this is Russian instead of 0)
Re-enter: %0 (this is the number 0)

Because the code copied from the Internet may contain inexplicable invisible characters or minor language symbols, which look exactly like real escape characters.