Plugin jQuery para formatação de inputs

jQuery-decimalFormat.js

// the semi-colon before function invocation is a safety net against concatenated 
// scripts and/or other plugins which may not be closed properly.
;(function ( $, window, undefined ) {

  // undefined is used here as the undefined global variable in ECMAScript 3 is
  // mutable (ie. it can be changed by someone else). undefined isn't really being
  // passed in so we can ensure the value of it is truly undefined. In ES5, undefined
  // can no longer be modified.

  // window and document are passed through as local variables rather than globals
  // as this (slightly) quickens the resolution process and can be more efficiently
  // minified (especially when both are regularly referenced in your plugin).

  // Create the defaults once
  var pluginName = 'decimalFormat',
  document = window.document,
  defaults = {
  	decimal: '.',
  	thousand: ','
  },
  lPad = function(str, padString, length) {
  	while (str.length < length) {str = padString + str}
  	return str;
  }

  formatValor = function(valor){
  	var result = [], i, n="" ;
  	if( isNaN(+valor) || !valor) return '0,00';
  	if(valor < 0){
  		valor *= -1;
  		n='-';
  	}
  	valor = (+valor).toFixed(2).split('.');
  	for(i = +valor[0] ; i ; i = Math.floor(i/1000)){
  		result.unshift("" + lPad((i%1000)+"",'0' ,3 ));
  	}
  	result[0] = +result[0] + "";
  	return n+result.join('.') + "," + valor[1];
  };

  // The actual plugin constructor
  function Plugin( element, options ) {
  	this.element = element;

    // jQuery has an extend method which merges the contents of two or 
    // more objects, storing the result in the first object. The first object
    // is generally empty as we don't want to alter the default options for
    // future instances of the plugin
    this.options = $.extend( {}, defaults, options) ;

    this._defaults = defaults;
    this._name = pluginName;

    this.init();
}

Plugin.prototype.init = function () {
    // Place initialization logic here
    // You already have access to the DOM element and the options via the instance, 
    // e.g., this.element and this.options

    var regex = /^[\d,\.]*$/i,
    replaceRegex = /\D/g;
    
    $(this.element).on('keydown', function(event){
    	if ( event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || event.keyCode == 27 || event.keyCode == 13 || 
             // Allow: Ctrl+A
             (event.keyCode == 65 && event.ctrlKey === true) || 
             // Allow: home, end, left, right
             (event.keyCode >= 35 && event.keyCode <= 39)) {
                 // let it happen, don't do anything
             return;
         }
         else {
            // Ensure that it is a number and stop the keypress
            if (event.shiftKey || (event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode > 105 )) {
            	event.preventDefault(); 
            }   
        }
    });

    $(this.element).on('change', function(event){
    	this.value = formatValor(this.value.replace(replaceRegex, ''));
    });
};

  // A really lightweight plugin wrapper around the constructor, 
  // preventing against multiple instantiations
  $.fn[pluginName] = function ( options ) {
  	return this.each(function () {
  		if (!$.data(this, 'plugin_' + pluginName)) {
  			$.data(this, 'plugin_' + pluginName, new Plugin( this, options ));
  		}
  	});
  }

}(jQuery, window));