//把值按3個為一組加入,號,小數點內保留兩位
為txtprojectcost增加keyup和blur方法
   $("#txtprojectcost").keyup(function(){                             
                if(isNaN(this.value.replaceAll(",",""))){
                  this.value = this.value.replaceAll(",","").replace(/[^\d.]/g, "");

                  this.value=this.value.replaceAll(",","").replace(/^\./g, "");//首位不能為.
                  this.value=this.value.replaceAll(",","").replace(/^00/g, "");//首兩位不能為00
}
             
            }).blur(function(){
                jiSuan(this);
            });

  function jiSuan(obj)
 {
  var newStr = "";
  var count = 0;

obj.value=obj.value.replaceAll(",","");
if(obj.value=="") return;
  if(obj.value.indexOf(".")==-1)
  {
   for(var i=obj.value.length-1;i>=0;i--)
   {
    if(count % 3 == 0 && count != 0)
    {
     newStr = obj.value.charAt(i) + "," + newStr;
    }
    else
    {
     newStr = obj.value.charAt(i) + newStr;
    }
    count++;
   }
   obj.value = newStr + ".00";
  }
  else
  {
      for(var i=obj.value.indexOf(".")-1;i>=0;i--)
   {
    if(count % 3 == 0 && count != 0)
    {
     newStr = obj.value.charAt(i) + "," + newStr;
    }
    else
    {
     newStr = obj.value.charAt(i) + newStr;
    }
    count++;
   }

   obj.value = newStr + (obj.value + "00").substr((obj.value + "00").indexOf("."),3);
  }

 }
由于給值加入逗號后正則判斷會認為值不符合，所以需要替換到字符串內所有的,號,AFindText要替換掉得字符，ARepText 替換為
 String.prototype.replaceAll = stringReplaceAll;
       function stringReplaceAll(AFindText,ARepText){
 
        var st='/'+AFindText+"/gi";
    
        return  this.replace(eval("/"+AFindText+"/ig"),ARepText);
    }