function stringFilter (input)
{
	s = input.value;
	filteredValues = ",`~ !@#$%^&*()_+[]{}\|;':<>/?ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";     // Characters stripped out
 
	var i;
	var returnString = "";
	for (i = 0; i < s.length; i++)
        {  // Search through string and append to unfiltered values to returnString.
		var c = s.charAt(i);
		if (filteredValues.indexOf(c) == -1) returnString += c;
	}
 
	return returnString;
}
 
function addCommas (obj) {
 
  n = stringFilter(obj); 
  decimals=0; 
 
  decimals=(decimals>=0?decimals:2)
  var t = Math.floor(n*Math.pow(10,decimals)+0.5).toString();
  while (t.length < decimals+1) t = "0"+t;
    var i = t.length-decimals;
    if(decimals)t = t.substr(0,i)+"."+t.substr(i); // insert decimal separator (a dot or comma)
    for (i -= 3; i > 0; i -= 3) t = t.substr(0,i)+","+t.substr(i); // insert thousands separators (commas or dots)
    obj.value = '$' + t;
}