(PHP 4 >= 4.0.6, PHP 5, PHP 7)
mb_strwidth — Return width of string
$str
   [, string $encoding = mb_internal_encoding()
  ] )
   Returns the width of string str,
   where halfwidth characters count as 1, and fullwidth
   characters count as 2.
  
The fullwidth characters are: U+1100-U+115F, U+11A3-U+11A7, U+11FA-U+11FF, U+2329-U+232A, U+2E80-U+2E99, U+2E9B-U+2EF3, U+2F00-U+2FD5, U+2FF0-U+2FFB, U+3000-U+303E, U+3041-U+3096, U+3099-U+30FF, U+3105-U+312D, U+3131-U+318E, U+3190-U+31BA, U+31C0-U+31E3, U+31F0-U+321E, U+3220-U+3247, U+3250-U+32FE, U+3300-U+4DBF, U+4E00-U+A48C, U+A490-U+A4C6, U+A960-U+A97C, U+AC00-U+D7A3, U+D7B0-U+D7C6, U+D7CB-U+D7FB, U+F900-U+FAFF, U+FE10-U+FE19, U+FE30-U+FE52, U+FE54-U+FE66, U+FE68-U+FE6B, U+FF01-U+FF60, U+FFE0-U+FFE6, U+1B000-U+1B001, U+1F200-U+1F202, U+1F210-U+1F23A, U+1F240-U+1F248, U+1F250-U+1F251, U+20000-U+2FFFD, U+30000-U+3FFFD. All other characters are halfwidth characters.
strThe string being decoded.
encodingThe encoding
parameter is the character encoding. If it is omitted, the internal character
encoding value will be used.
   The width of string str.