I often need to edit files with different encodings, which can't be detected automatically (for example, how distinguish between cp866 and cp1251?). So when the desired file was loaded with a wrong encoding, I used to type:

:e ++enc=<what_was_really_needed> %:p

The following function makes it easier:

function! ChangeFileencoding()
  let encodings = ['cp1251', 'koi8-u', 'cp866']
  let prompt_encs = []
  let index = 0
  while index < len(encodings)
    call add(prompt_encs, index.'. '.encodings[index])
    let index = index + 1
  endwhile
  let choice = inputlist(prompt_encs)
  if choice >= 0 && choice < len(encodings)
    execute 'e ++enc='.encodings[choice].' %:p'
  endif
endf
nmap <F8> :call ChangeFileencoding()<CR>

Further, it can be improved by populating the list of encodings from &fileencodings.

You can also set file encoding automatically from a modeline.

CommentsEdit

Also see Reloading a file using a different encoding.

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