Vim (vimscript) get exact character under the cursor

Question

I am getting the character under the cursor in vimscript the following way:

getline(\'.\')[col(\'.\')-1] 

It works exactly like it should,

Answer 1

Another way to get the character index under cursor that deal with both ASCII and non-ASCII characters is the like the following:

function! CharAtIdx(str, idx) abort                                       
  " Get char at idx from str. Note that this is based on character index  
  " instead of the byte index.                                            
  return strcharpart(a:str, a:idx, 1)                                     
endfunction
                                                                          
function! CursorCharIdx() abort                                           
  " A more concise way to get character index under cursor.               
  let cursor_byte_idx = col('.')                                          
  if cursor_byte_idx == 1                        
    return 0                      
  endif                                                                   
                             
  let pre_cursor_text = getline('.')[:col('.')-2]                         
  return strchars(pre_cursor_text)                                        
endfunction                                                               

Then if you want to get char under cursor, use the following command:

let cur_char_idx = CursorCharIdx()
let cur_char = CharAtIdx(getline('.'), cur_char_idx)

See also this post on how to get pre-cursor char.