Why does my mapping of <C-PageX> to :bY not work in gvim?

Question

In my .vimrc file, I have the following two lines:

noremap! <C-PageDown> :bnext <CR>
noremap! <C-PageUp>   :bprev <CR>

but they do not work! In insert mode, typing

<C-v><C-PageDown>

returns

<C-PageDown>

(literally) and similarly so for <C-PageUp> and if I try to execute the command I get

:bnext

(plus a newline). In normal mode there's no effect. Thus, I know that the key map isn't being gobbled up by X or my shell but what else could be the problem? Other key maps work fine.

Answer 1

Could it be, because this keys are already used by vim for switching tab pages? See the description in vims documentation

Answer 2

The n in :noremap is for normal mode, so it won't work in insert mode. If you want it to work in insert mode, use :imap. If you were trying to use <C-V> to make it work in insert mode, I think you were looking for <C-O>.

Answer 3

Solved!

noremap  <C-PageDown>           :bnext <CR>
noremap  <C-PageUp>             :bprev <CR>
inoremap <C_PageDown> <C-\><C-O>:bnext <CR>
inoremap <C_PageUp>   <C-\><C-O>:bprev <CR>

In insert mode, anything on the RHS of the key mapping is inserted literally so we need to use <C-O> which enters normal mode for a single command. The <C-\> prevents the cursor from moving leftward which occurs when invoking <C-O> at the end of a line.

Also note that you can't have a space between <C-O> and :bnext else it will be eaten by <C-O>.