在 vim 中，使用单个命令切换文本文件中所有字符的大小写

Question

In Vim I need to convert all lowercase to uppercase and all uppercase to lowercase with a single command. So if my text file looks like this..

Hello World

.. it needs to be toggled to look like this..

hELLO wORLD

I know :%s/[az]/\U&/g will change all lowercase to uppercase and that :%s/[AZ]/\L&/g will change all uppercase to lowercase. But how would I write that to do both at the same time?

In addition I know if my cursor is at the top of the file VG~ will toggle case everything but that's not the answer I need. Thank you.

Answer 1

<Esc>1GVG~

Explanation:

<Esc> — return to Normal mode; just in case we're in Insert mode or Command line
1G — jump to the 1st line
V — start Visual mode
G — jump to the last line extending selection
~ — toggle case in the selection

Or

<Esc>1Gg~G

g~<motion> — change case during motion; the motion is G (jump to last line)

Docs: http://vimdoc.sourceforge.net/htmldoc/change.html#~

Answer 2

Looks like you already know everything you need. ggVG~ marks all your code and toggles the case. If you want a single command you can either use:

:nnoremap <keybinding> ggVG~

or use this function, which does the same, but keeps your current position in the file:

function ToggleCase()
    exec "normal! mqHmw"
    exec "normal! ggVG~"
    exec "normal! 'wzt`q"
endfunction
command ToggleCase silent call ToggleCase()

the first and last exec mark your position in the file and restore them, after the case toggling. See: :h marks

type :ToggleCase to use the function. Of cause you can bind this to a keybinding as well.

:nnoremap <keybinding> :ToggleCase<cr>

Answer 3

Since you mentioned using a single command and you mentioned some :%s/.../ substitutions, I'll offer this one:

:%normal! g~~

This will run the g~~ command to switch case of a single line, for each line of the buffer.

Answer 4

One more way to accomplish this, if you're ok adopting a plug-in, is to use the kana/vim-textobj-entire plug-in for a text object for the entire buffer.

As the plug-in README.md file says:

Though these are trivial operations (eg ggVG ), text object versions are more handy, because you do not have to be conscious of the cursor position (eg vae ).

With this plug-in installed and enabled, you can switch case of the whole buffer with:

g~ae