resources/jquery/jquery.byteLength.js

   1 /**
   2  * jQuery.byteLength
   3  *
   4  * Calculate the byte length of a string (accounting for UTF-8).
   5  *
   6  * @author Jan Paul Posma, 2011
   7  */
   8 jQuery.byteLength = function ( str ) {
   9
  10         // This basically figures out how many bytes a UTF-16 string (which is what js sees)
  11         // will take in UTF-8 by replacing a 2 byte character with 2 *'s, etc, and counting that.
  12         // Note, surrogate (\uD800-\uDFFF) characters are counted as 2 bytes, since there's two of them
  13         // and the actual character takes 4 bytes in UTF-8 (2*2=4). Might not work perfectly in
  14         // edge cases such as illegal sequences, but that should never happen.
  15         return str
  16                 .replace( /[\u0080-\u07FF\uD800-\uDFFF]/g, '**' )
  17                 .replace( /[\u0800-\uD7FF\uE000-\uFFFF]/g, '***' )
  18                 .length;
  19 };