JS Realization of Digital Format Thousand Position Mutual Conversion Method

Examples are as follows:

/**
 *  Convert digital format to thousandth 
 *@param{Object}num
 */
function commafy(num){
  if((num+"").Trim()==""){
   return"";
  }
  if(isNaN(num)){
   return"";
  }
  num = num+"";
  if(/^.*\..*$/.test(num)){
   varpointIndex =num.lastIndexOf(".");
   varintPart = num.substring(0,pointIndex);
   varpointPart =num.substring(pointIndex+1,num.length);
   intPart = intPart +"";
    var re =/(-?\d+)(\d{3})/
    while(re.test(intPart)){
     intPart =intPart.replace(re,"$1,$2")
    }
   num = intPart+"."+pointPart;
  }else{
   num = num +"";
    var re =/(-?\d+)(\d{3})/
    while(re.test(num)){
     num =num.replace(re,"$1,$2")
    }
  }
  return num;
}

/**
 *  Remove the thousandth 
 *@param{Object}num
 */

function delcommafy(num){
  if((num+"").Trim()==""){
   return"";
  }
  num=num.replace(/,/gi,'');
  returnnum;
}