Natural Sort for JavaScript - http://www.davekoelle.com/alphanum.html

alphanum.js

/* alphanum.js (C) Brian Huisman
 * Based on the Alphanum Algorithm by David Koelle
 * The Alphanum Algorithm is discussed at http://www.DaveKoelle.com
 *
 * Distributed under same license as original
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

/* ********************************************************************
 * Alphanum Array prototype version
 *  - Much faster than the sort() function version
 *  - Ability to specify case sensitivity at runtime is a bonus
 *
 */
Array.prototype.alphanumSort = function(caseInsensitive) {
  for (var z = 0, t; t = this[z]; z++) {
    this[z] = new Array();
    var x = 0, y = -1, n = 0, i, j;

    while (i = (j = t.charAt(x++)).charCodeAt(0)) {
      var m = (i == 46 || (i >=48 && i <= 57));
      if (m !== n) {
        this[z][++y] = "";
        n = m;
      }
      this[z][y] += j;
    }
  }

  this.sort(function(a, b) {
    for (var x = 0, aa, bb; (aa = a[x]) && (bb = b[x]); x++) {
      if (caseInsensitive) {
        aa = aa.toLowerCase();
        bb = bb.toLowerCase();
      }
      if (aa !== bb) {
        var c = Number(aa), d = Number(bb);
        if (c == aa && d == bb) {
          return c - d;
        } else return (aa > bb) ? 1 : -1;
      }
    }
    return a.length - b.length;
  });

  for (var z = 0; z < this.length; z++)
    this[z] = this[z].join("");
}


/* ********************************************************************
 * Alphanum sort() function version - case sensitive
 *  - Slower, but easier to modify for arrays of objects which contain
 *    string properties
 *
 */
function alphanum(a, b) {
  function chunkify(t) {
    var tz = new Array();
    var x = 0, y = -1, n = 0, i, j;

    while (i = (j = t.charAt(x++)).charCodeAt(0)) {
      var m = (i == 46 || (i >=48 && i <= 57));
      if (m !== n) {
        tz[++y] = "";
        n = m;
      }
      tz[y] += j;
    }
    return tz;
  }

  var aa = chunkify(a);
  var bb = chunkify(b);

  for (x = 0; aa[x] && bb[x]; x++) {
    if (aa[x] !== bb[x]) {
      var c = Number(aa[x]), d = Number(bb[x]);
      if (c == aa[x] && d == bb[x]) {
        return c - d;
      } else return (aa[x] > bb[x]) ? 1 : -1;
    }
  }
  return aa.length - bb.length;
}


/* ********************************************************************
 * Alphanum sort() function version - case insensitive
 *  - Slower, but easier to modify for arrays of objects which contain
 *    string properties
 *
 */
function alphanumCase(a, b) {
  function chunkify(t) {
    var tz = new Array();
    var x = 0, y = -1, n = 0, i, j;

    while (i = (j = t.charAt(x++)).charCodeAt(0)) {
      var m = (i == 46 || (i >=48 && i <= 57));
      if (m !== n) {
        tz[++y] = "";
        n = m;
      }
      tz[y] += j;
    }
    return tz;
  }

  var aa = chunkify(a.toLowerCase());
  var bb = chunkify(b.toLowerCase());

  for (x = 0; aa[x] && bb[x]; x++) {
    if (aa[x] !== bb[x]) {
      var c = Number(aa[x]), d = Number(bb[x]);
      if (c == aa[x] && d == bb[x]) {
        return c - d;
      } else return (aa[x] > bb[x]) ? 1 : -1;
    }
  }
  return aa.length - bb.length;
}