oldVal=0;

function validation(userValue){

        keyHit=document.getElementById(userValue).value;
        lastHit=keyHit.charAt(keyHit.length-1);
  
        if( isNaN(keyHit)||keyHit < 0){
            document.getElementById(userValue).value=oldVal;
        }
        else
            oldVal=keyHit; 
}

function addCommas(number)
{   
  if(number.value!=""){
    nStr=(number.value.search(/\./)==-1)?number.value:parseFloat(number.value).toFixed(2)
	nStr += '';
	x = nStr.split('.');
	x1 = x[0];
	x2 = x.length > 1 ? '.' + x[1] : '';
	var rgx = /(\d+)(\d{3})/;
	while (rgx.test(x1)) {
		x1 = x1.replace(rgx, '$1' + ',' + '$2');
	}
	number.value= x1 + x2;
  }
  else
    number.value="";
}
	

function removeComma(number){
  if(number.value!=""){
    num=number.value;
    num= num.toString().replace(/\,/g,"");
    number.value=num;
    number.select();  
    oldVal=num;
  }
  else
    number.value="";
  return true;
}