JavaScript Object and String enhancements. Each usable standalone.

Object.prototype.sizeof.js

if (!Object.prototype.sizeof) {
  Object.defineProperty(Object.prototype, 'sizeof', {
    value: function() {
      var counter = 0;
      for (index in this) counter++;
      return counter;
    },
    enumerable: false
  });
}

String.prototype.htmlEntities.js

if (!String.prototype.htmlEntities) {
  Object.defineProperty(String.prototype, 'htmlEntities', {
    value: function() {
      return String(this).replace(/&/g, '&').replace(/>/g, '>').replace(/"/g, '"');
    },
    enumerable: false
  });
}

String.prototype.isHex.js

if (!String.prototype.isHex) {
  Object.defineProperty(String.prototype, 'isHex', {
    value: function() {
      return this.substring(0, 1) == '#' && (this.length == 4 || this.length == 7) && /^[0-9a-fA-F]+$/.test(this.slice(1));
    },
    enumerable: false
  });
}

String.prototype.pxToInt.js

if (!String.prototype.pxToInt) {
  Object.defineProperty(String.prototype, 'pxToInt', {
    value: function() {
      return parseInt(this.split('px')[0]);
    },
    enumerable: false
  });
}

String.prototype.reverse.js

if (!String.prototype.reverse) {
  Object.defineProperty(String.prototype, 'reverse', {
    value: function() {
      return this.split('').reverse().join('');
    },
    enumerable: false
  });
}

String.prototype.stripNonAlpha.js

if (!String.prototype.stripNonAlpha) {
  Object.defineProperty(String.prototype, 'stripNonAlpha', {
    value: function() {
      return this.replace(/[^A-Za-z ]+/g, "");
    },
    enumerable: false
  });
}

String.prototype.stripTags.js

if (!String.prototype.stripTags) {
  Object.defineProperty(String.prototype, 'stripTags', {
    value: function() {
      return this.replace(/<\/?[^>]+>/gi, '');
    },
    enumerable: false
  });
}

String.prototype.trim.js

if (!String.prototype.trim) {
  Object.defineProperty(String.prototype, 'trim', {
    value: function() {
      return this.replace(/^\s*/, "").replace(/\s*$/, "");
    },
    enumerable: false
  });
}

String.prototype.wordCount.js

if (!String.prototype.wordCount) {
  Object.defineProperty(String.prototype, 'wordCount', {
    value: function() {
      return this.split(' ').length;
    },
    enumerable: false
  });
}