My vim rc

.vimrc

" When started as "evim", evim.vim will already have done these settings, bail
" out.
if v:progname =~? "evim"
  finish
endif

" Get the defaults that most users want.
source $VIMRUNTIME/defaults.vim

if has("vms")
  set nobackup		" do not keep a backup file, use versions instead
else
  set backup		" keep a backup file (restore to previous version)
  if has('persistent_undo')
    set undofile	" keep an undo file (undo changes after closing)
  endif
endif

if &t_Co > 2 || has("gui_running")
  " Switch on highlighting the last used search pattern.
  set hlsearch
endif

" Put these in an autocmd group, so that we can delete them easily.
augroup vimrcEx
  au!

  " For all text files set 'textwidth' to 78 characters.
  autocmd FileType text setlocal textwidth=78
augroup END

" Add optional packages.
"
" The matchit plugin makes the % command work better, but it is not backwards
" compatible.
" The ! means the package won't be loaded right away but when plugins are
" loaded during initialization.
if has('syntax') && has('eval')
  packadd! matchit
endif

set background=dark
set mouse=""
set number
set cursorline
set autoindent
set ignorecase

au FileType vim setlocal ts=2 st=4 shiftwidth=4 expandtab
au FileType javascript setlocal ts=2 st=2 shiftwidth=2 expandtab

" let shift-tab to unindent
inoremap <S-Tab> <C-d>

filetype plugin indent on

" let insert mode absolute line number
"   , normal mode relative line number
autocmd InsertEnter * :set norelativenumber
autocmd InsertLeave * :set relativenumber

" keymap for F8 for highlight search result
map <F8> :set hls!<CR>

" Buffer keymap
nnoremap <silent> [b :bprevious<CR>
nnoremap <silent> ]b :bnext<CR>
nnoremap <silent> [B :bfirst<CR>
nnoremap <silent> ]B :blast<CR>

" -------------
" netrw setting
" -------------
let g:netrw_banner=0
let g:netrw_liststyle=3
let g:netrw_winsize=20



let g:netrw_is_open=0
function! ToggleNetrw()
    if g:netrw_is_open
        let g:netrw_is_open=0
        let i = bufnr("$")
        while (i >= 1)
            if (getbufvar(i, "&filetype") == "netrw")
	        silent exe "bwipeout " . i
            endif
            let i -= 1
        endwhile
    else
        let g:netrw_is_open=1
        silent Lexplore
    endif
endfunction

noremap <silent> <F2> :call ToggleNetrw()<CR>