How does VIM add CTRL+/ as a shortcut key

  question, vim

I want to use ctrl+/ as the shortcut key for the current line comment
Addnmap <C-/> ,ccInvalid, but backslash \ is possible
I hope you can help me look at it.

Ctrl+/ cannot be used as a shortcut key in vim.

You can’t map Ctrl-/ in Vim because the only “Ctrl+printable key” characters which can be reliably mapped in Vim are those defined by the (already rather old) ASCII standard, which means the only printable keys which have a Ctrl counterpart are 0x3F to 0x5F plus the lowercase letters, as follows:

Ctrl+? (0x3F) = DEL (0x7F)
Ctrl+(key 0x40-0x5F) = subtract 0x40 from the printable character
Ctrl+lowercase = Ctrl+ the corresponding uppercase.

Nothing else. No Ctrl+digit and no Ctrl+slash (where / = 0x2F).

BTW, the above also explains why Vim cannot discriminate between

Ctrl-I and Tab (both 0x09, HT)
Ctrl-M and Enter (both 0x0D, CR)
Ctrl-[ and Esc (both 0x1B, ESC)

Too lazy to translate, fromHere.